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1.
Int J Hyperthermia ; 38(1): 1349-1358, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34486913

RESUMO

OBJECTIVES: To develop and assess nonenhanced MRI-based radiomics model for the preoperative prediction of nonperfused volume (NPV) ratio of uterine leiomyomas after high-intensity focused ultrasound (HIFU) treatment. METHODS: Two hundred and five patients with uterine leiomyomas treated by HIFU were enrolled and allocated to training (N =164) and testing cohorts (N = 41). Pyradiomics was used to extract radiomics features from T2-weighted images and apparent diffusion coefficient (ADC) map generated from diffusion-weighted imaging (DWI). The clinico-radiological model, radiomics model, and radiomics-clinical model which combined the selected radiomics features and clinical parameters were used to predict technical outcomes determined by NPV ratios where three classification groups were created (NPV ratio ≤ 50%, 50-80% or ≥ 80%). The receiver operating characteristic (ROC) curve, area under the curve (AUC), and calibration and decision curve analyses were performed to illustrate the prediction performance and clinical usefulness of model in the training and testing cohorts. RESULTS: The multi-parametric MRI-based radiomics model outperformed T2-weighted imaging (T2WI)-based radiomics model, which achieved an average AUC of 0.769 (95% confidence interval [CI], 0.701-0.842), and showed satisfactory prediction performance for NPV ratio classification. The radiomics-clinical model demonstrated best prediction performance for HIFU treatment outcome, with an average AUC of 0.802 (95% CI, 0.796-0.850) and an accuracy of 0.762 (95% CI, 0.698-0.815) in the testing cohort, compared to the clinico-radiological and radiomics models. The decision curve also indicated favorable clinical usefulness of the radiomics-clinical model. CONCLUSIONS: Nonenhanced MRI-based radiomics has potential in the preoperative prediction of NPV ratio for HIFU ablation of uterine leiomyomas.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Leiomioma , Imagem de Difusão por Ressonância Magnética , Humanos , Leiomioma/diagnóstico por imagem , Leiomioma/cirurgia , Imageamento por Ressonância Magnética , Curva ROC , Estudos Retrospectivos
2.
J Coll Physicians Surg Pak ; 31(9): 1024-1029, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34500515

RESUMO

OBJECTIVE: To compare the effect of different quantification methods of ADC values in the evaluation of breast lesions and compare contralateral normal breast tissue ADC value by calculating ADC ratios. STUDY DESIGN: Descriptive study. Place and Duration of the Study: Sisli Etfal Training and Research Hospital, Turkey, between February 2019 and December 2020. METHODOLOGY: Two hundred and forty-six breast MRI scans with DWI of the patients with biopsy proven unilateral breast lesions were studied. ADC measurements were done by placing ROI. Two ADC values and two ADC ratios were obtained by different methods. The diagnostic accuracies of these four techniques were compared. RESULTS: Mean ADC values and ratios of benign and malignant lesions were statistically significant in all of four methods to quantify ADC (p< 0.001). Highest positive value and negative predictive value, and diagnostic accuracy rates were achieved when the most restricted part ADC value was calculated. However; highest sensitivity rate and negative predictive value were achieved by calculating the ratio of darkest point ADC to contralateral breast tissue. Positive predictive value, negative predictive value, and diagnostic accuracy rate of calculated ADC values and ratios were higher when lesions were larger than the mean size (3.15 mm2). CONCLUSION: Highest diagnostic accuracy rate was obtained with most restricted part ADC value. Obtained ratios by calculating contralateral breast tissue ADC value did not improve the diagnostic accuracy rate. Positive and negative predictive values and diagnostic accuracy rates of ADC values and ratios increased as the lesion size increased. Key Words: Breast mass, Diffusion weighted imaging, ADC value, ADC ratio, Normalised ADC.


Assuntos
Neoplasias da Mama , Imagem de Difusão por Ressonância Magnética , Biópsia , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Valor Preditivo dos Testes , Sensibilidade e Especificidade
3.
Anticancer Res ; 41(9): 4549-4554, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475082

RESUMO

BACKGROUND/AIM: Tumor infiltrating lymphocytes (TILs) are an important prognostic factor in brain metastasis (BM). This study elucidated associations between apparent diffusion coefficient (ADC) texture analysis and TIL in BM. PATIENTS AND METHODS: Eleven patients with BM were retrospectively included into the study. TIL levels were analyzed with Leucocyte-common antigen staining. Clinical routine magnetic resonance imaging was used to calculate the texture features. RESULTS: ADC GrayLevelNonUniformity correlated with TILs of the stromal compartment (r=0.67, p=0.02). ADC HighGrayLevelRunEmphasis and ADC Coarseness showed associations with TILs of the tumoral compartment (r=-0.60, p=0.04 and r=0.68, p=0.02, respectively). CONCLUSION: ADC texture features correlated with TIL levels in BM. ADC texture features could aid in reflecting the complex tumor-micromilieu in a non-invasive manner.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/secundário , Imagem de Difusão por Ressonância Magnética/métodos , Linfócitos do Interstício Tumoral/metabolismo , Adulto , Idoso , Neoplasias Encefálicas/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos
4.
Medicine (Baltimore) ; 100(35): e27131, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477159

RESUMO

ABSTRACT: The evaluation of bone disease in multiple myeloma (MM) is an important topic in imaging. This study retrospectively investigated whole-body diffusion-weighted imaging (WB-DWI) in the evaluation of bone marrow infiltration and treatment response in MM.A total of 126 patients with MM who underwent WB-DWI between January 2016 and December 2020 were enrolled. All the patients received 4-course induction chemotherapy. WB-DWI was performed before and after chemotherapy to measure the apparent diffusion coefficient (ADC) values. According to gender and Revised International Staging System (RISS) staging groups, the relationship between ADC value and bone marrow plasma cell infiltration ratio before treatment were explored using Spearman and Pearson correlation coefficients. Comparison of ADC values before and after treatment according to different chemotherapy regimens and treatment response was performed by 2-independent samples non-parametric tests and t test.There was a negative correlation between the ADC value and the degree of bone marrow infiltration and this was statistically significant (r = -0.843, P < .001). In different gender and RISS groups, ADC value before treatment was negatively correlated with the proportion of plasma cell infiltration (male, r = -0.849; female, r = -0.836; Stage I, r = -0.659; Stage II, r = -0.870; Stage III, r = -0.745; all P < .001). The ADC values of all subjects increased to varying degrees after 4-course induction chemotherapy, including different chemotherapy regimens and treatment responses (all P < .05 except for progressive disease group).The ADC value was negatively correlated with the degree of bone marrow infiltration in different gender and RISS stages. The ADC value increased after treatment, but it was not consistent with progressive disease group. The increase of ADC value may indicate the disease burden and outcome of MM induced chemotherapy.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Mieloma Múltiplo/diagnóstico por imagem , Imagem Corporal Total/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
J Appl Clin Med Phys ; 22(9): 324-331, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34343402

RESUMO

PURPOSE: Manual delineation of a rectal tumor on a volumetric image is time-consuming and subjective. Deep learning has been used to segment rectal tumors automatically on T2-weighted images, but automatic segmentation on diffusion-weighted imaging is challenged by noise, artifact, and low resolution. In this study, a volumetric U-shaped neural network (U-Net) is proposed to automatically segment rectal tumors on diffusion-weighted images. METHODS: Three hundred patients of locally advanced rectal cancer were enrolled in this study and divided into a training group, a validation group, and a test group. The region of rectal tumor was delineated on the diffusion-weighted images by experienced radiologists as the ground truth. A U-Net was designed with a volumetric input of the diffusion-weighted images and an output of segmentation with the same size. A semi-automatic segmentation method was used for comparison by manually choosing a threshold of gray level and automatically selecting the largest connected region. Dice similarity coefficient (DSC) was calculated to evaluate the methods. RESULTS: On the test group, deep learning method (DSC = 0.675 ± 0.144, median DSC is 0.702, maximum DSC is 0.893, and minimum DSC is 0.297) showed higher segmentation accuracy than the semi-automatic method (DSC = 0.614 ± 0.225, median DSC is 0.685, maximum DSC is 0.869, and minimum DSC is 0.047). Paired t-test shows significant difference (T = 2.160, p = 0.035) in DSC between the deep learning method and the semi-automatic method in the test group. CONCLUSION: Volumetric U-Net can automatically segment rectal tumor region on DWI images of locally advanced rectal cancer.


Assuntos
Aprendizado Profundo , Neoplasias Retais , Imagem de Difusão por Ressonância Magnética , Humanos , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Neoplasias Retais/diagnóstico por imagem , Reto/diagnóstico por imagem
7.
Zhongguo Gu Shang ; 34(8): 743-9, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34423618

RESUMO

OBJECTIVE: To investigate the application value of apparent diffusion coefficient (ADC) and signal intensity ratio (SIR) of MR diffusion-weighted imaging (DWI) in quantitative evaluation of lumbar spine osteoporosis. METHODS: A total of 175 patients with lumbar spine diseases who received dualenergy X-ray absorption (DXA) bone mineral density (BMD), routine MRI and DWI of the lumbar spine from May 2017 to October 2019 were selected. According to the T-value of DXA, the patients were divided into osteoporosis group (64 cases), osteopenia group (53 cases) and normal bone mass group (58 cases). The ADC and SIR values of L2-L4 were measured and compared among the three groups and the correlation between ADC, SIR and BMD was analyzed. The ROC curve was used to evaluate the differential diagnosis value of ADC and SIR for osteoporosis, osteopenia and normal bone mass. RESULTS: There were statistically significant differences in ADC and SIR values among three groups (F=41.386, 37.114, all P=0.000). The ADC value of the osteoporosis group was lower than that of the osteopenia group and the normal bone mass group, and the difference was statistically significant (t=3.540, 9.069, P=0.001, 0.000);the SIR value of the osteoporosis group was higher than that of the osteopenia group and the normal bone mass group, and the difference was statistically significant (t=5.083, 8.523, all P=0.000). Spearman correlation analysis showed that ADC value was positively correlated with BMD (r=0.313, P=0.004);SIR value was negatively correlated with BMD (r=- 0.589, P=0.000). Receiver operator characteristic (ROC) curve analysis showed that the area under curve (AUC), sensitivity andspecificity of ADC and SIR in the diagnosis of lumbar osteoporosis and osteopenia were 0.742, 89.1% , 52.8% and 0.729, 89.1%, 50.9% respectively (P=0.000);the AUC, sensitivity and specificity of ADC and SIR in the diagnosis of lumbar osteoporosis and normal bone mass were 0.815, 100.0%, 50.0% and 0.856, 65.6%, 93.1%, respectively (P=0.000);the AUC, sensitivity and specificity of ADC and SIR in the diagnosis of lumbar osteoporosis were 0.78, 89.1%, 51.4% and 0.795, 50.0% and 94.6% respectively (P=0.000);All have a certain diagnostic value. CONCLUSION: ADC and SIR can better reflect the BMD of patients with lumbar diseases, and can quantitatively evaluate the vertebral body of osteoporosis, which play an important role in the diagnosis of lumbar osteoporosis.


Assuntos
Osteoporose , Imagem de Difusão por Ressonância Magnética , Humanos , Vértebras Lombares/diagnóstico por imagem , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Osteoporose/diagnóstico por imagem
8.
Eur J Radiol ; 142: 109889, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34388627

RESUMO

OBJECTIVE: To evaluate the feasibility, image quality, and apparent diffusion coefficient (ADC) values of diffusion-weighted imaging (DWI) using echo planar imaging (EPI) with Compressed SENSE (EPICS-DWI) of the abdomen and to compare them with conventional single-shot EPI with parallel imaging (PI) technique (PI-DWI). MATERIALS AND METHODS: This prospective study included 46 participants with known or suspected upper abdominal diseases (19 men and 27 women, mean age, 68 years) who underwent MRI. DWI acquisition was performed using free-breathing two-dimensional fat-suppressed PI-DWI and EPICS-DWI with SENSE or compressed sensing (CS) factor, 3.0. Moreover, image noise and contour of liver and pancreas were qualitatively evaluated using a five-point scale. The mean ADC value and standard deviation (SD) of the liver, pancreas, and spleen were measured, and the coefficient of variation (CV) was calculated. Qualitative and quantitative parameters were compared between PI-DWI and EPICS-DWI using the Wilcoxon test. RESULTS: The mean image quality scores for image noise and contour of liver and pancreas were higher in EPICS-DWI compared with PI-DWI (P < 0.0001). Moreover, the mean ADC values of the liver and pancreas were higher in EPICS-DWI compared with PI-DWI (P < 0.0001), but that of spleen was not significantly different. The mean SD and CV of the liver, pancreas, and spleen were lower in EPICS-DWI compared with PI-DWI (P < 0.0001-0.032). CONCLUSION: EPICS-DWI could be feasible in MRI of the abdomen and significantly improve image quality compared with PI-DWI in aggressive setting. ADC value measurements were higher in EPICS-DWI compared with PI-DWI.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imagem Ecoplanar , Abdome/diagnóstico por imagem , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes
9.
J Int Med Res ; 49(7): 3000605211029766, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34334006

RESUMO

A 28-year-old female patient was hospitalized primarily because of "intermittent fever for 28 days aggravated by systemic rashes, oral ulcer, and edema in both eyelids for 5 days." During treatment, convulsions and loss of consciousness occurred. Magnetic resonance imaging (MRI) of the head revealed an abnormal signal with shadows in the bilateral frontal, parietal, temporal, and occipital lobes; cerebellar hemispheres; and basal nodes, with high signal intensity on T2 weighted imaging (T2WI), on fluid-attenuated inversion-recovery, and of the apparent diffusion coefficient and low signal intensity on T1WI and diffusion weighted imaging. Therefore, the patient was diagnosed with systemic lupus erythematosus (SLE) with reversible posterior encephalopathy syndrome (RPES). Intravenous high-dose methylprednisolone and cyclophosphamide were administered for blood pressure control, which effectively controlled the disease. Therefore, when patients with SLE and hypertension or renal insufficiency or those receiving high-dose methylprednisolone or immunosuppressants suddenly present with neurologic abnormalities, a diagnosis of RPES must be considered, and head MRI is the first choice for diagnosis of this disease. In terms of treatment, the blood pressure should be quickly controlled, and the primary disease should be aggressively treated.


Assuntos
Encefalopatias , Lúpus Eritematoso Sistêmico , Síndrome da Leucoencefalopatia Posterior , Adulto , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Imageamento por Ressonância Magnética , Síndrome da Leucoencefalopatia Posterior/complicações , Síndrome da Leucoencefalopatia Posterior/diagnóstico por imagem , Síndrome da Leucoencefalopatia Posterior/tratamento farmacológico
10.
Zhonghua Zhong Liu Za Zhi ; 43(8): 872-877, 2021 Aug 23.
Artigo em Chinês | MEDLINE | ID: mdl-34407594

RESUMO

Objective: To explore the diagnostic value of synthetic magnetic resonance imaging (syMRI) quantitative parameters for benign and malignant breast lesions. Methods: From September 2018 to March 2019, a total of 43 cases of breast lesions which were confirmed by surgery and pathology in Cancer Hospital, Chinese Academy of Medical Sciences were enrolled in this study. All patients underwent syMRI sequence scans before and after enhancement except for conventional T2WI, DWI, and enhancement scans. GE AW4.7 workstation was used to generate syMRI parameter maps (T1, T2, proton density mappings), and ITK-SNAP software was used to delineate the volume of interest. The T1, T2, PD values before and after dynamic contrast enhanced (DCE) were obtained, and the change values of each parameter were calculated. Meanwhile, the apparent diffusion coefficient (ADC) and time intensity curve (TIC) of the lesions were measured. The differences of each parameter value were compared between benign and malignant breast lesions, and the receiver operating characteristic (ROC) curve was used to analyze the diagnostic performance of each parameter. Results: Among the 43 enrolled cases, 13 were benign and 30 were malignant. Among the syMRI parameters, the pre-enhancement parameters including T1pre (median 1 663.07 ms), T2pre (median 103.33 ms), post-enhancement parameters ΔT1 (median 1 022.68 ms) and ΔT2 (median 27.67 ms) of benign group, significantly higher than those of the malignant group (the medians were 1 141.74, 92.53, 664.95, and 16.19 ms, respectively, P<0.05). The ADC value of the benign group (median 1.66×10(-3)mm(2)/s) was significantly higher than that of the malignant group (median 1.00×10(-3)mm(2)/s, P<0.05). The benign group included 6 cases of TIC curve type Ⅰ, 5 cases of type Ⅱ, and 2 cases of type Ⅲ. The malignant group included 2 cases of TIC curve type Ⅰ, 17 cases of type Ⅱ, and 11 cases of type Ⅲ. The difference between the two groups was statistically significant (P<0.05). The area under the ROC curve (AUC) of T1pre before DCE was 0.869, higher than 0.806 of ADC and 0.697 of TIC. When the best cut-off value of 1 282.94 ms was chosen, the sensitivity and specificity of diagnosis were 76.9% and 93.3%, respectively. The combination of T1pre and T2pre can further improve the diagnostic performance (AUC=0.908). Conclusions: Among the syMRI quantitative parameters, T1pre, T2pre, ΔT1 and ΔT2 have good value for the differential diagnosis of benign and malignant breast lesions. T1pre has the best diagnostic performance, and the combination of T1pre and T2pre can further improve the diagnostic performance.


Assuntos
Neoplasias da Mama , Meios de Contraste , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Imageamento por Ressonância Magnética , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
11.
Ann Palliat Med ; 10(7): 8112-8122, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34353096

RESUMO

BACKGROUND: The aim of this study was to assess the value of different 1.5 T MRI apparent diffusion coefficient (ADC) and exponential apparent diffusion coefficient (EADC) values in diagnosing the stages of liver cirrhosis. Sprague-Dawley (SD) rats were randomly divided into the experimental group and the control group. METHODS: The experimental group was injected with thioacetamide intraperitoneally 3 times per week. After routine MR scanning, diffusion-weighted imaging (DWI) was processed by spin echo-echo planar imaging (SE-EPI) to generate the ADC value and EADC image. The liver ADC and EADC values of rats were measured in the control and experimental groups, followed by Masson staining and hematoxylin and eosin staining. Furthermore, immunohistochemistry was performed to detect Ki-67 and PCNA expression in liver tissues. RESULTS: In the control group, the differences in ADC and EADC values between the liver fibrosis and cirrhosis group were different. The ADC values of the liver fibrosis stage I-II, III-IV, and cirrhosis rats in the experimental group were lower than the control group, while the EADC values were higher than the control group. The ADC values of the liver fibrosis stage III-IV group and cirrhosis nodules group were lower than the control group. There were significant differences in EADC values between the cirrhotic nodule groups and the control group. CONCLUSIONS: DWI-ADC values showed a negative correlation between SD rat liver fibrosis and cirrhosis pathology classification.


Assuntos
Imagem de Difusão por Ressonância Magnética , Cirrose Hepática , Animais , Antígeno Ki-67 , Cirrose Hepática/diagnóstico por imagem , Espectroscopia de Ressonância Magnética , Antígeno Nuclear de Célula em Proliferação , Ratos , Ratos Sprague-Dawley
12.
Nat Commun ; 12(1): 4894, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385454

RESUMO

White matter structural connections are likely to support flow of functional activation or functional connectivity. While the relationship between structural and functional connectivity profiles, here called SC-FC coupling, has been studied on a whole-brain, global level, few studies have investigated this relationship at a regional scale. Here we quantify regional SC-FC coupling in healthy young adults using diffusion-weighted MRI and resting-state functional MRI data from the Human Connectome Project and study how SC-FC coupling may be heritable and varies between individuals. We show that regional SC-FC coupling strength varies widely across brain regions, but was strongest in highly structurally connected visual and subcortical areas. We also show interindividual regional differences based on age, sex and composite cognitive scores, and that SC-FC coupling was highly heritable within certain networks. These results suggest regional structure-function coupling is an idiosyncratic feature of brain organisation that may be influenced by genetic factors.


Assuntos
Algoritmos , Encéfalo/fisiologia , Conectoma/métodos , Modelos Neurológicos , Rede Nervosa/fisiologia , Adulto , Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Rede Nervosa/anatomia & histologia , Rede Nervosa/diagnóstico por imagem , Adulto Jovem
13.
J Stroke Cerebrovasc Dis ; 30(9): 105944, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34271279

RESUMO

Ten days after SARS-Cov2 reinfection with mild gastrointestinal symptoms and headache that occurred 2 months after an initial infection, a previously healthy 37-year-old woman developed fluctuating facial and upper limb paresthesia and weakness. Diffusion-weighted magnetic resonance imaging revealed ischemic lesions in the right parietal region of different stages within the same vascular territory. A cerebral angiography demonstrated an isolated focal arteriopathy with no other arterial involvement. Focal cerebral arteriopathy is exceedingly rare among adults and most commonly triggered by varicella-zoster virus reactivation. We present a case of focal cerebral arteriopathy in a patient with a recent reinfection with SARS-CoV-2.


Assuntos
COVID-19/complicações , Doenças Arteriais Cerebrais/etiologia , AVC Isquêmico/etiologia , Reinfecção , Adulto , COVID-19/diagnóstico , COVID-19/virologia , Angiografia Cerebral , Doenças Arteriais Cerebrais/diagnóstico por imagem , Doenças Arteriais Cerebrais/tratamento farmacológico , Imagem de Difusão por Ressonância Magnética , Terapia Antiplaquetária Dupla , Feminino , Humanos , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/tratamento farmacológico , Angiografia por Ressonância Magnética , Inibidores da Agregação Plaquetária/administração & dosagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento
14.
Eur J Radiol ; 142: 109829, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34252867

RESUMO

PURPOSE: To investigate the diagnostic performance of the overall Vesical Imaging Reporting and Data System (VI-RADS) score and its individual magnetic resonance imaging (MRI) parameters in assessing grade and muscle invasiveness of bladder cancer (BC). METHODS: This IRB-approved retrospective, single-center, cross-sectional study included patients with BC wo underwent 3 Tesla preoperative multiparametric (mp)-MRI including T2-weighted (T2w), diffusion weighted imaging (DWI) and dynamic contrast enhanced (DCE) sequences. An independent evaluation according to VI-RADS was performed by two radiologists in separate sessions, blinded to histological findings. RESULTS: The mean age of 59 included patients was 68.2 (±13.6 standard deviation) years. Among bladder cancer patients, 26 (51%) were identified as high grade and 14 (27.5%) as muscle invasive urothelial carcinomas in histological sections. The area under the curve (AUC) for the overall VI-RADS score to predict muscle invasion was 0.986 (R1) and 0.992 (R2). The AUC to diagnose high grade bladder cancer was 0.908 (R1) and 0.905 (R2). There was no significance difference between the AUC of single parameters (T2w, DWI and DCE) compared to the total VI-RADS score (P > 0.05, respectively). Upon multivariate logistic regression, only the T2w VI-RADS score contributed independently to the diagnosis of high grade and muscle invasive bladder cancer (P = 0.001 (R1) and P = 0.0022 (R2) for high grade cancer; P = 0.0007 (R1) and P = 0.0019 (R2) for muscle invasiveness). CONCLUSION: VI-RADS provides high diagnostic accuracy to diagnose high grade and muscle invasive BC. Our results suggest, that mp-MRI parameters provide overlapping information and for sake of clinical simplicity, a biparametric, contrast free image acquisition may be approached without sacrificing diagnostic accuracy.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Neoplasias da Bexiga Urinária , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Imagem de Difusão por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/diagnóstico por imagem
15.
Eur J Radiol ; 142: 109869, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34303149

RESUMO

PURPOSE: To develop a model based on histogram parameters derived from intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) for predicting the nodal staging of rectal cancer (RC). MATERIAL AND METHODS: A total of 95 RC patients who underwent direct surgical resection were enrolled in this prospective study. The nodal staging on conventional magnetic resonance imaging (MRI) was evaluated according to the short axis diameter and morphological characteristics. Histogram parameters were extracted from apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) maps. Multivariate binary logistic regression analysis was conducted to establish models for predicting nodal staging among all patients and those underestimated on conventional MRI. RESULTS: The combined model based on multiple maps demonstrated superior diagnostic performance to single map models, with an area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy of 0.959, 94.3%, 88.3%, and 90.5%, respectively. The AUC of the combined model was significantly higher than that of the conventional nodal staging (P < 0.001). Additionally, 85.0% of the underestimated patients had suspicious lymph nodes with 5-8 mm short-axis diameter. The histogram model for these subgroups of patients showed good diagnostic efficacy with an AUC, sensitivity, specificity, and accuracy of 0.890, 100%, 75%, and 80.5%. CONCLUSION: The histogram model based on IVIM-DWI could improve the diagnostic performance of nodal staging of RC. In addition, histogram parameters of IVIM-DWI may help to reduce the uncertainty of nodal staging in underestimated patients on conventional MRI.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias Retais , Humanos , Imageamento por Ressonância Magnética , Movimento (Física) , Estudos Prospectivos , Neoplasias Retais/diagnóstico por imagem
16.
Eur J Radiol ; 142: 109855, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34303150

RESUMO

PURPOSE: This article reviews the frequency, upgrade rate and valuable imaging characteristics for predicting the histologic upgrade risks of high-risk lesions on MRI, so as to provide a reference for the management of the lesions. METHODS: A comprehensive search for relevant publications from January 2011 to January 2021 was conducted in the PubMed database. The frequency, upgrade rate and valuable imaging characteristics for predicting the upgrade risks of high-risk lesions on MRI included in the articles were reviewed, and the management of high-risk lesions was provided with a reference according to the review results. RESULTS AND CONCLUSIONS: In terms of management options, Atypical ductal hyperplasia (ADH) and Lobular neoplasia (LN) (the top two high-risk lesions with the highest upgrade rate and frequency) were treated with surgical resection. However, the final treatment decision for other high-risk lesions should be made by a multidisciplinary committee. In terms of the value of breast MRI in predicting the upgrade risks of high-risk lesions, the lesions that were confirmed to upgrade after surgery showed some enhancement characteristics, especially for ADH and LN. At the same time, Dynamic contrast-enhanced MRI (DCE-MRI) has a high negative predictive value (NPV) in predicting the upgrade risks of the high-risk lesions, hence misdiagnosis and overtreatment can be reduced. Diffusion-weighted imaging (DWI) and relative apparent diffusion coefficient (rADC) can be used to predict the upgrade risks of the lesions, and the ADC of upgraded lesions is lower than that of non-upgraded lesions. However, these conclusions should be confirmed by further studies.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Mama , Neoplasias da Mama/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos
17.
Nat Commun ; 12(1): 4237, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244483

RESUMO

Brain network hubs are both highly connected and highly inter-connected, forming a critical communication backbone for coherent neural dynamics. The mechanisms driving this organization are poorly understood. Using diffusion-weighted magnetic resonance imaging in twins, we identify a major role for genes, showing that they preferentially influence connectivity strength between network hubs of the human connectome. Using transcriptomic atlas data, we show that connected hubs demonstrate tight coupling of transcriptional activity related to metabolic and cytoarchitectonic similarity. Finally, comparing over thirteen generative models of network growth, we show that purely stochastic processes cannot explain the precise wiring patterns of hubs, and that model performance can be improved by incorporating genetic constraints. Our findings indicate that genes play a strong and preferential role in shaping the functionally valuable, metabolically costly connections between connectome hubs.


Assuntos
Encéfalo/fisiologia , Conectoma , Redes Reguladoras de Genes , Rede Nervosa/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Conjuntos de Dados como Assunto , Imagem de Difusão por Ressonância Magnética , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Modelos Genéticos , Gêmeos
18.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(4): 698-705, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34323052

RESUMO

Objective: To explore the radiomics features of T2 weighted image (T2WI) and readout-segmented echo-planar imaging (RS-EPI) plus difusion-weighted imaging (DWI), to develop an automated mahchine-learning model based on the said radiomics features, and to test the value of this model in predicting preoperative T staging of rectal cancer. Methods: The study retrospectively reviewed 131 patients who were diagnosed with rectal cancer confirmed by the pathology results of their surgical specimens at West China Hospital of Sichuan University between October, 2017 and December, 2018. In addition, these patients had preoperative rectal MRI. Tumor regions from preoperative MRI were manually segmented by radiologists with the ITK-SNAP software from T2WI and RS-EPI DWI images. PyRadiomics was used to extract 200 features-100 from T2WI and 100 from the apparent diffusion coefficient (ADC) calculated from the RS-EPI DWI. MWMOTE and NEATER were used to resample and balance the dataset, and 13 cases of T 1-2 stage simulation cases were added. The overall dataset was divided into a training set (111 cases) and a test set (37 cases) by a ratio of 3∶1. Tree-based Pipeline Optimization Tool (TPOT) was applied on the training set to optimize model parameters and to select the most important radiomics features for modeling. Five independent T stage models were developed accordingly. Accuracy and the area under the curve ( AUC) of receiver operating characteristic (ROC) were used to pick out the optimal model, which was then applied on the training set and the original dataset to predict the T stage of rectal cancer. Results: The performance of the the five T staging models recommended by automated machine learning were as follows: The accuracy for the training set ranged from 0.802 to 0.838, sensitivity, from 0.762 to 0.825, specificity, from 0.833 to 0.896, AUC, from 0.841 to 0.893, and average precision (AP) from 0.870 to 0.901. After comparison, an optimal model was picked out, with sensitivity, specificity and AUC for the training set reaching 0.810, 0.875, and 0.893, respectively. The sensitivity, specificity and AUC for the test set were 0.810, 0.813, and 0.810, respectively. The sensitivity, specificity and AUC for the original dataset were 0.810, 0.830, and 0.860, respectively. Conclusion: Based on the radiomics data of T2WI and RS-EPI DWI, the model established by automated machine learning showed a fairly high accuracy in predicting rectal cancer T stage.


Assuntos
Imagem Ecoplanar , Neoplasias Retais , China , Imagem de Difusão por Ressonância Magnética , Humanos , Aprendizado de Máquina , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/cirurgia , Estudos Retrospectivos
19.
J Clin Neurosci ; 90: 99-104, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34275589

RESUMO

Occlusion of the artery of Percheron (AoP) causes bithalamic paramedian infarct (BTPI). Although it can be diagnosed easily in its pure form, it can be underdiagnosed in cases with concomitant extrathalamic acute infarcts (plus-BTPI) as it may be difficult to determine whether BTPI is due to occlusion of AoP or two different paramedian arteries even with conventional angiography. This study was performed to highlight plus-BTPI that could result from occlusion of AoP rather than of two distinct paramedian arteries using topographic evaluation of bithalamic infarcts. We retrospectively reviewed imaging and clinical databases for patients admitted to radiology department between 2013 and 2019. Two radiologists independently evaluated the results of imaging studies, and findings reached by consensus were used in the analysis. This retrospective review yielded 34 patients with bithalamic infarct. Each affected thalamic vascular region was investigated separately. Any patient could have more than 2 different vascular zone infarct. The affected thalamic vascular territories were paramedian (n = 24), inferolateral (n = 13), anterior (n = 10), and posterior (n = 7). When we evaluated bithalamic infarcts in terms of symmetrically affected territories, the distribution of symmetric affected territories was as: paramedian (n = 18), inferolateral (n = 2), anterior (n = 1), and posterior (n = 1). BTPI had a 4.5-fold higher frequency than the sum of symmetric involvement of other territories (p = 0.0552, OR = 4.5,95%CI 0.93-21.5). In addition, mesencephalic involvement was only observed in BTPI, and not in other patterns (p < 0.001). The fact that in bilateral thalamic infarcts the symmetric involvement of paramedic territory is significantly higher and mesencephalic involvement is seen only in BTPI can suggest that plus-BPTI may develop due to AoP occlusion rather than occlusion of two distinct paramedian arteries.


Assuntos
Arteriopatias Oclusivas/diagnóstico por imagem , Infarto Cerebral/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
J Comput Assist Tomogr ; 45(3): 367-373, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34297508

RESUMO

OBJECTIVE: The objective of this study was to compare the image quality and apparent diffusion coefficient (ADC) of diffusion-weighted imaging (DWI) with modified reduced field of view (FOV) based on 2-dimensional (2D)-selective radiofrequency excitations by tilting the excitation plane in prostate with reduced FOV using parallel-transmit-accelerated 2D-selective radiofrequency excitation and single-shot echo planar imaging (ssEPI). METHODS: Fifty patients who underwent multiparametric magnetic resonance imaging including 3 DWIs were included. Two observers independently performed qualitative image analyses using 5-point scale. Apparent diffusion coefficient measurements were performed for quantitative analysis. RESULTS: Modified reduced FOV provided the highest qualitative scores for all categories compared with reduced FOV and ssEPI (P < 0.000). Both reduced FOV DWIs showed higher ADC values compared with ssEPI (P < 0.001); however, the ADC ratios between the lesion and peripheral zone were not significantly different (all P > 0.05). CONCLUSIONS: The modified reduced FOV DWI showed better overall image quality, differentiability of anatomic regions, and lesion conspicuity with fewer artifacts compared with DWI with reduced FOV and ssEPI.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Próstata/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Imagem Ecoplanar , Humanos , Masculino , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética Multiparamétrica , Variações Dependentes do Observador , Estudos Retrospectivos , Razão Sinal-Ruído
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