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1.
J Comput Assist Tomogr ; 43(5): 755-761, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31609294

RESUMO

OBJECTIVES: This study aimed to evaluate the feasibility of intravoxel incoherent motion diffusion-weighted magnetic resonance imaging (DW-MRI) in detecting bowel inflammation in patients with Crohn disease (CD). METHODS: Sixteen patients who underwent intravoxel incoherent motion DW-MRI for CD and colonoscopy were recruited. Seventy-nine bowel segments were selected, and their mean D, D*, f, and apparent diffusion coefficient (ADC) values were measured. The receiver operating characteristic curve was performed to distinguish inflamed from normal bowel. RESULTS: The mean D, D*, f, and ADC values of inflamed bowel were significantly lower than those of normal bowel (P < 0.05). The area under the receiver operating characteristic curve for f (0.906) and ADC values (0.924) was greater than that for D (0.709) or D* values (0.686) for differentiating inflamed bowel from normal bowel (P < 0.05). CONCLUSIONS: Intravoxel incoherent motion DW-MRI is a feasible technique for detecting inflammation in CD patients. The ADC and f values have more potential than the D and D* values.


Assuntos
Doença de Crohn/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Colonoscopia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Inflamação/diagnóstico por imagem , Masculino , Estudos Prospectivos
2.
Can Assoc Radiol J ; 70(4): 457-465, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31582328

RESUMO

PURPOSE: The aim of this study is to evaluate the diagnostic contribution of diffusion-weighted magnetic resonance imaging (MRI) and computed tomography (CT) to distinguish extramural venous invasion (EMVI) in rectal adenocarcinoma. MATERIALS AND METHODS: Fifty-eight patients who had been diagnosed with rectal adenocarcinoma (30 patients with EMVI and 28 patients without EMVI) were enrolled in the study. Apparent diffusion coefficient (ADC) values of the tumour and the EMVI (+) vein, the lengths of the tumours were measured on MRI. The diameters of the superior rectal vein (SRV)-inferior mesenteric vein (IMV) and distant metastatic spread were evaluated on CT. The ability of these findings to detect EMVI was assessed using receiver operating characteristic (ROC) analysis. Pathology was accepted as the reference test for EMVI. RESULTS: Mean diameters of the SRV (4.9 ± 0.9 mm vs 3.7 ± 0.8 mm) and IMV (6.9 ± 0.8 mm vs 5.4 ± 0.9 mm) were significantly larger (P < .001) and tumour ADC values were significantly lower (0.926 ± 0.281 × 10-3 mm2/s vs 1.026 ± 0.246 × 10-3 mm2/s; P = .032) in EMVI (+) patients. Diameters of 3.95 mm for the SRV (area under the curve [AUC] ± standard error [SE]: 0.851 ± 0.051, P < .001, sensitivity: 93.3%, specificity: 67.9%) and 5.95 mm for the IMV (AUC ± SE: 0.893 ± 0.040, P < .001, sensitivity: 93.3%, specificity: 71.4%) and an ADC value of 0.929 × 10-3 mm2/s (AUC ± SE: 0.664 ± 0.072, P = .032 sensitivity: 76.7%, specificity: 57.1%) were found to be cutoff values, determined by ROC analysis, for detection of EMVI. Distant metastases were significantly more prevalent in EMVI (+) patients (P < .001). CONCLUSION: The measurement of ADC values and SRV-IMV diameters seems to have contribution for diagnosis of EMVI in rectal adenocarcinoma. EMVI (+) patients appear to have higher risks of distant metastases at diagnosis.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Invasividade Neoplásica/diagnóstico por imagem , Invasividade Neoplásica/patologia , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reto/irrigação sanguínea , Reto/diagnóstico por imagem , Estudos Retrospectivos
3.
Can Assoc Radiol J ; 70(4): 416-423, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31604596

RESUMO

PURPOSE: To evaluate whole-lesion 3D-histogram apparent diffusion coefficient (ADC) metrics for assessment of pancreatic malignancy. METHODS: Forty-two pancreatic malignancies (36 pancreatic adenocarcinoma [PDAC], 6 pancreatic neuroendocrine [PanNET]) underwent abdominal magnetic resonance imaging (MRI) with diffusion-weighted imaging before endoscopic ultrasound biopsy or surgical resection. Two radiologists independently placed 3D volumes of interest to derive whole-lesion histogram ADC metrics. Mann-Whitney tests and receiver operating characteristic analyses were used to assess metrics' diagnostic performance for lesion histology, T-stage, N-stage, and grade. RESULTS: Whole-lesion ADC histogram metrics lower in PDACs than PanNETs for both readers (P ≤ .026) were mean ADC (area under the curve [AUC] = 0.787-0.792), mean of the bottom 10th percentile (mean0-10) (AUC = 0.787-0.880), mean of the 10th-25th percentile (mean10-25) (AUC = 0.884-0.917) and mean of the 25th-50th percentile (mean25-50) (AUC = 0.829-0.829). For mean10-25 (metric with highest AUC for identifying PDAC), for reader 1 a threshold > 0.94 × 10-3 mm2/s achieved sensitivity 94% and specificity 83%, and for reader 2 a threshold > 0.82 achieved sensitivity 97% and specificity 67%. Metrics lower in nodal status ≥ N1 than N0 for both readers (P ≤ .043) were mean0-10 (AUC = 0.789-0.822) and mean10-25 (AUC = 0.800-0.822). For mean10-25 (metric with highest AUC for identifying N0), for reader 1 a threshold <1.17 achieved sensitivity 87% and specificity 67%, and for reader 2 a threshold <1.04 achieved sensitivity 87% and specificity 83%. No metric was associated with T-stage (P > .195) or grade (P > .215). CONCLUSION: Volumetric ADC histogram metrics may serve as non-invasive biomarkers of pancreatic malignancy. Mean10-25 outperformed standard mean for lesion histology and nodal status, supporting the role of histogram analysis.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Biópsia Guiada por Imagem , Imagem Tridimensional , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias Pancreáticas/patologia
4.
Zhonghua Yi Xue Za Zhi ; 99(35): 2756-2760, 2019 Sep 17.
Artigo em Chinês | MEDLINE | ID: mdl-31550798

RESUMO

Objective: To analyze the diagnostic value of diffusion-weighted imaging (DWI) signal pattern in renal lesions with T(2)WI hypointensity. Methods: Retrospective analysis was performed on DWI imaging datasets of 135 renal lesions with hypointentsity on T(2)WI confirmed by surgery, biopsy, or follow-up in the First Medical Center of Chinese PLA General Hospital from February 2016 to February 2017.One hundred and thirty-five renal lesions,43 benign lesions(age from 28 to 70 years,mean age was 43.5 years, male 18 lesions and female 25 lesions) and 92 malignant lesions (age from 17 to 86 years, mean age was 54.1 years, male 62 lesions and female 30 lesions). DWI signal pattern was classified into six categories: homogeneously high signal, homogeneously low signal, heterogeneously high signal, high halo signal, high halo and nodular signal, and high nodular signal. The agreement between two observers were tested using kappa statistic. The statistical difference between DWI signal characteristics in benign and malignant lesions was analyzed with Chi-Square test. Diagnostic efficacy in differentiation of benign and malignant renal lesions using DWI signal pattern were calculated. Results: One hundred and thirty-five lesions were detected in 135 cases with T(2)WI hypointensity. There were 43 benign lesions and 92 malignant lesions. The agreement between two observers was very good (kappa value=0.878 6). In renal T(2)WI hypointensity lesions, the proportion of DWI homogeneous high signal, homogeneous low signal, heterogeneous high signal, high halo signal, high halo and nodular signal, high nodular signal was 4.7% (2/43), 25.6% (11/43), 30.2% (13/43), 18.6% (8/43), 11.6% (5/43), 9.3% (4/43), respectively. The proportion of malignant lesions was 10.9% (10/92), 0 (0/92), 17.4% (16/92), 13.0% (12/92), 56.5% (52/92) and 2.2% (2/92), respectively. The difference of high halo and nodules signal and homogeneous low signal was statistically significant (all P<0.01). The sensitivity, specificity, positive prediction value (PPV) and negative prediction value (NPV) of high halo and nodular signal for malignancy were 56.5% (52/92), 88.4%(38/43), 91.2% (52/57) and 48.7%(38/78), respectively and homogeneous low signal for benign lesions were 25.6% (11/43), 100.0% (92/92), 100.0% (11/11) and 74.2% (92/124), respectively. Conclusions: DWI signal features may facilitated the accurate diagnosis of renal lesions with T(2)WI hypointensity. Malignant lesions exhibit a higher propensity with high halo and nodular signal on DWI while benign lesions with homogeneous low signal.


Assuntos
Imagem de Difusão por Ressonância Magnética , Rim/diagnóstico por imagem , Rim/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias Renais/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
5.
Zhonghua Wei Chang Wai Ke Za Zhi ; 22(9): 891-895, 2019 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-31550830

RESUMO

The commonly used radiological examinations for gastrointestinal stromal tumor (GIST) include ultrasound, CT, magnetic resonance imaging and PET, which play important roles in the individualized treatment of GIST through the assistance of the detection, location, diagnose and differential diagnosis, biological behavior and risk evaluation, operation planning, therapeutic effects prediction and follow-up. Standardized predisposal, multi-planar reconstruction and multi-phase enhancement are of great significance in the detection of small GIST lesions. Differences in drainage vessels and enhancement characteristics of tumors are helpful in differentiating small intestinal GIST from pancreatic cancer, neuroendocrine tumors and other abdominal non-GIST tumors. Radiology can provide multiple indicators to qualitatively or quantitatively reflect the risk of GIST. Recent study found that the risk classification of GIST has correlation with necrosis, but not cystic degeneration. The risk stratification of GIST by dual-energy CT showed that CT value and standardized iodine concentration in arterial-venous and delayed phases of high-risk tumors were significantly higher than those of non-high-risk tumors. The correlation between tumor enhancement pattern and risk stratificationwas still controversial. Recently, the rise of radiomics and deep learning techniques provide new direction for risk assessment of GIST. Some studies used various models and parameters to predict the risk classifications of GIST and achieved AUC values above 0.85, and some results were also superior to conventional indicators and radiologists' subjective judgment in the prediction of exon 11 mutations, mitotic counts and survivals. Recent developments in PET and diffusion-weighted MRI provide more precise functional quantitative indicators for the prediction and early evaluation of the response of GIST to targeted therapy. These studies are constantly expanding our field of exploration, and prompting us to stride toward the goal of individualized treatment of GIST.


Assuntos
Tumores do Estroma Gastrointestinal , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Estadiamento de Neoplasias , Pesquisa/tendências , Tomografia Computadorizada por Raios X
6.
Can Assoc Radiol J ; 70(4): 441-451, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31561925

RESUMO

INTRODUCTION: To establish the diagnostic performance of the parameters obtained from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging at 3T in discriminating between non-clinically significant prostate cancers (ncsPCa, Gleason score [GS] < 7) and clinically significant prostate cancers (csPCa, GS ≥ 7) in the peripheral zone. MATERIALS AND METHODS: Twenty-six male patients with peripheral zone prostate cancer (PCa) who had undergone 3T multiparametric magnetic resonance imaging (MRI) scan prior to biopsy were included in the study and evaluated retrospectively. The GS was obtained by both standard 12-core transrectal ultrasound guided biopsy and targeted MRI-US fusion biopsy and then confirmed by prostatectomy, if available. For each confirmed tumour focus, DCE-derived quantitative perfusion metrics (Ktrans, Kep, Ve, initial area under the curve [AUC]), the apparent diffusion coefficient (ADC) value, and normalized versions of quantitative metrics were measured and correlated with the GS. RESULTS: Ktrans had the highest diagnostic accuracy value of 82% among the DCE-MRI parameters (AUC 0.90), and ADC had the strongest diagnostic accuracy value of 87% among the overall parameters (AUC 0.92). The combination of ADC and Ktrans have higher diagnostic performance with the area under the receiver operating characteristic curve being 0.98 (sensitivity 0.94; specificity 0.89; accuracy 0.92) compared to the individual evaluation of each parameter alone.The GS showed strong negative correlations with ADC (r = -0.72) and normalized ADC (r = -0.69) as well as a significant positive correlation with Ktrans (r = 0.69). CONCLUSION: The combination of Ktrans and ADC and their normalized versions may help differentiate between ncsPCa from csPCa in the peripheral zone.


Assuntos
Imagem por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Humanos , Interpretação de Imagem Assistida por Computador , Biópsia Guiada por Imagem , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(7): 805-812, 2019 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-31413220

RESUMO

OBJECTIVE: To evaluate the white-matter integrity and its correlation with cognitive function in patients with mild cognitive impairment (MCI) complicated with lacunar infarctions (LI) by diffusion tensor imaging (DTI) of magnetic resonance (MR).
 Methods: Twenty-six patients with MCI were selected including 14 patients with combined LI and 12 patients without combined LI, and 16 healthy volunteers were recruited as normal control. All subjects completed cognitive function assessment and DTI sequence of MR. Factional anisotropy (FA) and mean diffusivity (MD) values among the MCI with LI group (MCI-LI), the MCI without LI group (MCI-non LI), and the normal control group (NC) were compared, and the correlation between DTI parameters and cognition was determined by multiple linear stepwise regression.
 Results: Compared with the MCI-non LI group, the FA values were significantly decreased (P<0.05) and MD values were significantly increased (P<0.05) in the white matter fiber bundles (such as the left hippocampus of the cingulate tract, the frontal fascicle of the corpus callosum, the right inferior frontal occipital fascicle, and the right superior longitudinal fascicle) in the MCI-LI group. In the MCI-LI group, the FA value of right cingulate gyrus was significantly correlated with Activity of Daily Living Scale (ADL) score (B=-50.2, 95% CI -77.7 to -22.7, P=0.003); the FA value of left anterior thalamic radiation (B=443.8, 95% CI 222.9 to 664.8, P=0.001) and MD value of left inferior longitudinal tract (B=-318.5, 95% CI -534.7 to -102.3, P=0.009) were significantly correlated with Wechsler digit symbol substitution (WDSS) score; the FA value of left superior temporal lobe longitudinal tract was significantly correlated with Backward Digit Span (BDSP) score (B=12.5, 95% CI 1.5 to 23.4, P=0.030).
 Conclusion: The integrity of white matter is significantly destroyed in MCI patients with LI than that in MCI patients without LI, and there is a correlation between cognitive function and DTI parameters in some white matter tracts in MCI patients with LI.


Assuntos
Disfunção Cognitiva , Acidente Vascular Cerebral Lacunar , Substância Branca , Anisotropia , Encéfalo , Disfunção Cognitiva/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Humanos , Testes Neuropsicológicos
8.
Nervenarzt ; 90(10): 979-986, 2019 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-31407046

RESUMO

Important milestones of acute ischemic stroke (AIS) treatment were achieved in recent years. The results of two randomized controlled trials revealed that intravenous thrombolysis is efficacious for treatment of AIS patients with a symptom onset <9 h or an unknown time of symptom onset in the presence of beneficial patterns in advanced stroke imaging. These patterns comprise the evidence of salvageable tissue at risk of infarction in perfusion of computed tomography (so-called penumbral imaging) or a mismatch between the diffusion-weighted imaging (DWI) und fluid-attenuated inversion recovery (FLAIR) sequences in magnetic resonance imaging (so-called DWI-FLAIR mismatch). Another two randomized controlled trials resulted in evidence of a high effectiveness of mechanical thrombectomy using advanced imaging of selected AIS patients with a symptom onset <24 h or an unknown time window. This article provides an overview of the current study results and recommendations for the selection of imaging for evidence-based effective acute treatment of stroke patients.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Terapia Trombolítica , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/terapia , Imagem de Difusão por Ressonância Magnética , Fibrinolíticos/administração & dosagem , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia
9.
Medicine (Baltimore) ; 98(35): e16841, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31464910

RESUMO

RATIONALE: Multiple primary central nervous system lymphoma (MPCNSL) is a rare disease with differential diagnosis and treatment. As the underlying pathogenesis is not yet clarified, the early-stage clinical manifestations are occult and atypical. Also, the imaging manifestations are not specific, which is challenging for the clinical diagnosis and treatment. Therefore, additional clinical research is essential to understand the etiology of the disease. PATIENT CONCERNS: A 63-year-old male patient suffered from MPCNSLs but without typical clinical manifestations. The findings of the imaging examination were as follows. Magnetic resonance imaging (MRI) showed long T1 and T2 signal shadows in the right frontal lobe, right hippocampus, right cerebellar hemisphere, and the left occipital lobe. In addition, patchy T1-enhanced signal shadows were observed in the right frontal lobe and around the midline. Frontal lesions were detected in the magnetic resonance spectroscopy (MRS), Cho peak increased, and N-acetylaspartate (NAA) peak decreased. On the other hand, in the diffusion weighted imaging (DWI), apparent dispersion coefficient (ADC) showed low-value changes and high signal changes. The positron emission tomography-computed tomography (PET-CT) displayed radioactive accumulation in the right frontal lobe. DIAGNOSIS: Multiple primary central nervous system lymphoma. INTERVENTIONS: The patient received some conservative medical treatment, but his condition continued to worsen. Finally, he received a pathological biopsy, and refused further treatment after the result was reported. OUTCOMES: The patient died 1 week after biopsy, and the course of disease was about 100 days. LESSONS: PCNSL is a primary intracranial malignancy with low incidence and a high degree of malignancy and specificity in clinical manifestations. To facilitate early clinical treatment and improve the long-term survival of patients, it is necessary to master the imaging diagnostic methods and its features. The comprehensive application of multiple imaging examinations, such as CT, MRI, PET/CT, and PET/MRI, as well as, cerebrospinal fluid cytology can greatly improve the diagnosis of PCNSL.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Linfoma não Hodgkin/diagnóstico por imagem , Imagem Multimodal/métodos , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Imagem de Difusão por Ressonância Magnética , Evolução Fatal , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/patologia , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/patologia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons
10.
Medicine (Baltimore) ; 98(33): e16608, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31415354

RESUMO

The utility of multimodality molecular imaging for predicting treatment response and survival of patients with hypopharyngeal carcinoma remains unclear. Here, we sought to investigate whether the combination of different molecular imaging parameters may improve outcome prediction in this patient group.Patients with pathologically proven hypopharyngeal carcinoma scheduled to undergo chemoradiotherapy (CRT) were deemed eligible. Besides clinical data, parameters obtained from pretreatment 2-deoxy-2-[fluorine-18]fluoro-D-glucose positron emission tomography/computed tomography (F-FDG PET/CT), dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI), and diffusion-weighted MRI were analyzed in relation to treatment response, recurrence-free survival (RFS), and overall survival (OS).A total of 61 patients with advanced-stage disease were examined. After CRT, 36% of the patients did not achieve a complete response. Total lesion glycolysis (TLG) and texture feature entropy were found to predict treatment response. The transfer constant (K), TLG, and entropy were associated with RFS, whereas K, blood plasma volume (Vp), standardized uptake value (SUV), and entropy were predictors of OS. Different scoring systems based on the sum of PET- or MRI-derived prognosticators enabled patient stratification into distinct prognostic groups (P <.0001). The complete response rate of patients with a score of 2 was significantly lower than those of patients with a score 1 or 0 (14.7% vs 58.9% vs 75.7%, respectively, P = .007, respectively). The combination of PET- and DCE-MRI-derived independent risk factors allowed a better survival stratification than the TNM staging system (P <.0001 vs .691, respectively).Texture features on F-FDG PET/CT and DCE-MRI are clinically useful to predict treatment response and survival in patients with hypopharyngeal carcinoma. Their combined use in prognostic scoring systems may help these patients benefit from tailored treatment and obtain better oncological results.


Assuntos
Carcinoma/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/estatística & dados numéricos , Neoplasias Hipofaríngeas/diagnóstico por imagem , Imagem por Ressonância Magnética/estatística & dados numéricos , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Adulto , Carcinoma/mortalidade , Carcinoma/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Fluordesoxiglucose F18 , Humanos , Neoplasias Hipofaríngeas/mortalidade , Neoplasias Hipofaríngeas/patologia , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Imagem Multimodal/estatística & dados numéricos , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Compostos Radiofarmacêuticos , Taxa de Sobrevida
11.
Zhonghua Yi Xue Za Zhi ; 99(29): 2293-2296, 2019 Aug 06.
Artigo em Chinês | MEDLINE | ID: mdl-31434405

RESUMO

Objective: To explore the value of Clermont score in the detection of intestinal mucosal ulcer in Crohn's disease (CD). Methods: From May 2015 to August 2017, 45 patients (28 males and 17 females; median age was 25 years) were confirmed to have ileocolic CD by endoscopic and pathological examinations at Nanjing General Hospital. All patients underwent MRE and DWI examinations. Based on the appearance of intestinal mucosa endoscopically, intestine segments from 45 patients were divided into three groups, namely, no ulceration group (NU), superficial ulceration group (SU), and deep ulceration group (DU). Several factors contribute to Clermont score calculation. These included the measurement of intestinal wall thickness using MRE, evaluation of intestinal wall edema and ulceration by MRE, DWI performance and ADC value of each segment. One-way ANOVA was utilized to compare the Clermont scores and ADC values of the intestine segments among the three groups. The efficacy of the Clermont scores and ADC values in evaluating intestinal mucosal ulcer in CD was verified using ROC analysis. Results: A total of 137 intestine segments were included in the study with 30 cases in NU, 37 cases in SU, and 70 cases in DU.DU had the highest Clermont score (22.5±4.5),following were SU(15.8±3.5) and NU(10.2±1.3)(F=179.935,P<0.01).The ADC values of DU ((1.34±0.17)×10(-3)mm(2)/s) was lower than NU ((2.07±0.52)×10(-3)mm(2)/s) and SU ((1.52±0.23)×10(-3) mm(2)/s) (F=83.822,P<0.01).The AUCs of using Clermont score and ADC value in differentiating deep ulcerations were 0.887 and 0.733, respectively. Conclusions: Either Clermont score or ADC value can be used to evaluate mucosal ulcer in CD. Clermont score demonstrates a better efficacy than ADC value in detecting deep ulcerations.


Assuntos
Doença de Crohn , Adulto , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Mucosa Intestinal , Intestinos , Masculino , Úlcera
12.
J Assoc Physicians India ; 67(3): 46-51, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31304706

RESUMO

Abstract: Multiplanar MR imaging provides excellent spatial and contrast resolution necessary to differentiate the signal intensities of fatty (yellow) marrow elements from hematopoietic (red) marrow elements and hence it is useful for evaluation of various pathologies of bone marrow. Utilization of typical imaging features on conventional MR imaging techniques and other newer imaging techniques, such as diffusion-weighted imaging (DWI) and in- and out-of-phase MRI, for better characterisation of bone marrow pathologies has been highlighted. Aims and Objectives: To determine the prevalence of various bone marrow pathologies in spine. To study the MRI signal changes of bone marrow in various lesions such as anaemia, leukaemia, lymphomas and various bone marrow disorders. Materials and Methods: A total of 100 patients who were investigated between November 2012 and October 2014 were included. MRI spine studies were done on a 3.0 Tesla Philips Achieva Medical Systems. Observations and Results: In our study, out of 100 cases studied for various spinal pathologies, 48 patients were male and 52 were female indicating almost equal male to female distribution. Maximum cases were degenerative with most common site of involvement being lumbar followed by cervical region. There were only 3 cases of depletion disorder and no case with deposition disorder. The mean age group was 45.37 years, with the range being 9 years to 72 years. Maximum patients (n = 67) were found in the age group of 41-60. Conclusion: Various bone marrow disorders were classified and evaluated separately. A systematic approach to its evaluation by categorization is essential with prudent use of both conventional and problem-solving techniques, such as CSI and DWI, for accurate diagnosis and appropriate patient management. Conventional radiology depicts changes of an altered bony matrix while MRI displays changes at a cellular level and is well suited for imaging the bone marrow. MRI serves as a screening method in bone marrow disorders and the diagnosis is established in context with the clinical findings or by biopsy.


Assuntos
Doenças da Medula Óssea/diagnóstico por imagem , Medula Óssea , Imagem por Ressonância Magnética , Adulto , Criança , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Coluna Vertebral
13.
Medicine (Baltimore) ; 98(27): e16089, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31277105

RESUMO

To establish magnetic resonance imaging (MRI) features that differentiate residual tumors from postoperative surgical changes following the transsphenoidal approach of a pituitary adenoma.We analyzed residual enhancements at the tumor bed in 52 patients who underwent dynamic contrast-enhanced sella MRI within 48 hours after surgery and at 6 to 28 months. Patients were divided into 2 groups defined by either peripheral or nodular enhancement patterns. For each group, we measured the maximum thickness of the residual enhancing portion and compared differences in the residual tumor and postoperative changes.Among the tumors examined in the 52 patients, 19 residual tumors showed nodular (n = 16) and peripheral (n = 3) enhancement patterns, and 33 postoperative changes showed nodular (n = 3) and peripheral (n = 30) enhancement patterns. The mean residual tumor thickness was 7.1 mm (range, 2.9-16.8 mm) and 1.9 mm (range, 1.0-7.4 mm) in the postoperative change. Receiver operating characteristic curve analysis revealed that a 3.9-mm thickness was associated with 89% sensitivity, 97% specificity, and 94% accuracy for diagnosis of residual tumor.On immediate postoperative MRI, residual enhancement with greater than 3.9-mm thickness and nodular pattern suggest residual pituitary adenoma tumor.


Assuntos
Adenoma/patologia , Neoplasia Residual/patologia , Neoplasias Hipofisárias/patologia , Adenoma/diagnóstico por imagem , Adenoma/cirurgia , Adolescente , Adulto , Idoso , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/diagnóstico por imagem , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos , Sela Túrcica/diagnóstico por imagem , Adulto Jovem
14.
Einstein (Sao Paulo) ; 17(3): eAO4615, 2019 Jul 18.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31340245

RESUMO

OBJECTIVE: To compare qualitatively and quantitatively, in terms of image quality, a new biexponential diffusion sequence protocol with the standard monoexponential diffusion protocol on multiparametric prostate magnetic resonance imaging. METHODS: This study had a prospective data collection and cross-sectional analysis. Between August and November 2017, a total of 70 patients who underwent multiparametric prostate magnetic resonance imaging due to clinical suspicion of prostatic neoplasia were recruited. The images obtained were evaluated by two independent readers regarding subjective/qualitative criteria (six criteria) and objective/quantitative criteria (three criteria), always comparing the monoexponential to biexponential acquisition protocols. The results were compared by statistical analysis (interobserver agreement - Gwet coefficient; analysis of the qualitative variables - Stuart-Maxwell test; and analysis of the quantitative variables - Wilcoxon test). RESULTS: After exclusion of four patients, the final sample consisted of 66 patients. A good/excellent inter observer agreement was stablished for subjective criteria (except in one criteria). For the qualitative analysis the amount of good or excellent evaluations was higher for the monoexponential protocol (except in one category), with evidence of significant differences for three criteria (diffusion weighted imaging global quality; diffusion weighted imaging signal-to-noise ratio; and apparent diffusion coefficient signal-to-noise ratio). For the quantitative data analysis, the monoexponential protocol showed less variability of the anteroposterior diameters, meaning less distortion of the images, and better estimated signal-to-noise ratio. CONCLUSION: In our data, the quality of the images of the monoexponential standard diffusion sequence was qualitatively and quantitatively superior to those of the biexponential diffusion weighted imaging sequence.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética/normas , Neoplasias da Próstata/diagnóstico por imagem , Estudos Transversais , Humanos , Masculino , Variações Dependentes do Observador , Estudos Prospectivos , Padrões de Referência , Reprodutibilidade dos Testes , Razão Sinal-Ruído , Estatísticas não Paramétricas
15.
Medicine (Baltimore) ; 98(29): e16313, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31335678

RESUMO

We evaluated the relationships among functional imaging modality such as PET-CT and DW-MRI and lung adenocarcinoma pathologic heterogeneity, extent of invasion depth, and tumor cellularity as a marker of tumor microenvironment.In total, 74 lung adenocarcinomas were prospectively included. All patients underwent 18F-fluorodeoxyglucose (FDG) PET-CT and MRI before curative surgery. Pathology revealed 68 stage I tumors, 3 stage II tumors, and 3 stage IIIA tumors. Comprehensive histologic subtyping was performed for all surgically resected tumors. Maximum standardized uptake value (SUVmax) and ADC values were correlated with pathologic grade, extent of invasion, solid tumor size, and tumor cellularity.Mean solid tumor size (low: 1.7 ±â€Š3.0 mm, indeterminate: 13.9 ±â€Š14.2 mm, and high grade: 30.3 ±â€Š13.5 mm) and SUVmax (low: 1.5 ±â€Š0.2, indeterminate: 3.5 ±â€Š2.5, and high grade: 15.3 ±â€Š0) had a significant relationship with pathologic grade based on 95% confidence intervals (P = .01 and P < .01, respectively). SUVmax showed a strong correlation with tumor cellularity (R = 0.713, P < .001), but was not correlated with extent of invasion (R = 0.387, P = .148). A significant and strong positive correlation was observed among SUVmax values and higher cellularity and pathologic grade. ADC did not exhibit a significant relationship with tumor cellularity.Intratumor heterogeneity quantification using a multimodal-multiparametric approach might be effective when tumor volume consists of a real tumor component as well as a non-tumorous stromal component.


Assuntos
Adenocarcinoma de Pulmão , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Pulmonares , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Microambiente Tumoral , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/patologia , Adulto , Idoso , Correlação de Dados , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Reprodutibilidade dos Testes , República da Coreia , Carga Tumoral
16.
Medicine (Baltimore) ; 98(29): e16447, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31335699

RESUMO

To evaluate readout-segmented echoplanar (rsEPI) diffusion weighted imaging (DWI) for multiparametric (mp) magnetic resonance imaging (MRI) of the prostate compared to the established single-shot echoplanar imaging (ssEPI) sequence.One hundred ten consecutive patients with clinical suspicion of prostate cancer underwent mp prostate MRI using both, the ssEPI and the rsEPI DWI sequence. For an objective assessment, delineation of the prostate shape on both DWI sequences was compared to T2-weighted images by measuring organ diameters. Apparent diffusion coefficient (ADC) values, image contrast and contrast-to-noise ratio (CNR) were compared between the 2 sequences on a region-of-interest-based analysis. Diagnostic accuracy for quantitative ADC-values was calculated. Histopathology from MRI/ultrasound fusion-guided biopsy was used as reference standard. For a subjective assessment, 2 independent readers visually assessed image quality of both sequences using Likert-scales.Delineation of the prostate shape was more accurate with rsEPI compared to ssEPI. ADC values in target lesions were not significantly different but significantly higher in the surrounding normal prostatic tissue of the transition zone. CNR was comparable between ssEPI and rsEPI. Sensitivity and specificity were good for both sequences with 84/84% and 82/73% with a Youden selected cut-off of ADC = 0.971*10 mm/s for rsEPI and 1.017*10 mm/s for ssEPI. Anatomic artifacts were significantly less and SNR was lower on rsEPI compared to ssEPI in the subjective analysis.Delineation of the prostate shape was more accurate with rsEPI DWI than with ssEPI DWI with less anatomic artifacts and higher subjective SNR and image quality on rsEPI DW images. Diagnostic ability of quantitative ADC-values was not significantly different between the 2 sequences. Thus, rsEPI DWI might be more suitable for prostate MRI with regard to MRI-guided targeted biopsy and therapy planning.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Imagem Ecoplanar/métodos , Próstata , Neoplasias da Próstata , Idoso , Pesquisa Comparativa da Efetividade , Precisão da Medição Dimensional , Humanos , Biópsia Guiada por Imagem/métodos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Planejamento de Assistência ao Paciente , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Reprodutibilidade dos Testes
17.
Medicine (Baltimore) ; 98(30): e16360, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31348236

RESUMO

BACKGROUND AND OBJECTIVE: Ischemic stroke is a foremost cause for disability and death worldwide. This study is conducted in order to compare the diagnostic values between transcranial Doppler ultrasound (ultrasonography), computed tomography (CT), and magnetic resonance imaging (MRI) in patients suffering from ischemic stroke by performing a network meta-analysis. METHODS: We made use of Cochrane Library, PubMed, and Embase in order to obtain literature and papers. The combination analysis of both direct and indirect evidence in terms of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy was conducted so as to assess the odds ratios (ORs) and surface under the cumulative ranking curve (SUCRA) values of the seven different imaging methods. These imaging techniques include ultrasonography, computed tomography (traditional CT, computed tomography angiography [CTA], computed tomography perfusion [CTP]), and MRI (traditional MRI, diffusion-weighted imaging [DWI], magnetic resonance angiography), in order to properly diagnose ischemic stroke patients. RESULTS: Thirteen eligible diagnostic trials were enrolled into this network meta-analysis. The results of the traditional meta-analysis showed that among CT methods, CTP showed higher sensitivity, NPV, and accuracy; among MRI methods, DWI had relatively higher sensitivity, NPV, and accuracy. The results of network meta-analysis showed that DWI had relatively higher sensitivity, NPV, and accuracy when compared with traditional CT, CTA, magnetic resonance angiography and traditional MRI. CTP showed higher SUCRA among CT methods while DWI showed higher SUCRA among MRI methods. A cluster analysis revealed that DWI had the highest diagnostic value in terms of sensitivity, PPV, NPV, and accuracy amongst the aforementioned seven imaging techniques. CONCLUSION: This network meta-analysis provides supporting evidence to the idea that DWI has a higher diagnostic value regarding ischemic stroke among MRI methods, and CTP has a poor diagnostic value among CT methods, which provide therapeutic considerations for Ischemic stroke intervention.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia Doppler Transcraniana/métodos , Angiografia por Tomografia Computadorizada/métodos , Angiografia por Tomografia Computadorizada/normas , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética/normas , Humanos , Angiografia por Ressonância Magnética/métodos , Angiografia por Ressonância Magnética/normas , Imagem por Ressonância Magnética/normas , Meta-Análise em Rede , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X/normas , Ultrassonografia Doppler Transcraniana/normas
18.
Medicine (Baltimore) ; 98(26): e16212, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31261574

RESUMO

Patients with severe stroke and salvageable brain tissue at admission, who have higher glycaemic and blood pressure levels, may have a risk of iatrogenic hypoglycemia/iatrogenic hypotension. In this study, we examined the relationship between the presence of diffusion-weighted imaging (DWI)/perfusion-weighted imaging (PWI) mismatch, admission blood glucose level, and admission blood pressure level in patients who were admitted in the first 12 hours after onset. We studied 212 patients who were prospectively and consecutively registered to the stroke unit from 2006 to 2009. Correlations between mismatch and admission blood pressure level (ABPL) and admission blood glucose level (ABGL) were analyzed using multivariate logistic regression. Mismatch (P = .064, adjusted OR = 2.297, 95% CI, 0.953-5.536) was not associated with a high ABGL in the whole group. However, after excluding patients with diabetes mellitus (DM) (n = 67, 35%), mismatch (P = .033, adjusted OR = 3.801, 95% CI, 1.110-13.015), an impaired level of consciousness, use of anti-DM medication, glycated hemoglobin levels, and cardioembolic aetiology were independent predictors of a high ABGL. The presence of mismatch or proximal vessel occlusion was not associated with ABPL. Female sex (P = .048) and total anterior circulation stroke (P = .008) were independent predictors associated with a higher ABPL. We conclude that patients with hyperacute ischemic stroke with PWI/DWI mismatch are more likely to have hyperglycemia.


Assuntos
Imagem de Difusão por Ressonância Magnética , Angiografia por Ressonância Magnética , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Glicemia , Pressão Sanguínea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Estudos Prospectivos , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/fisiopatologia
19.
Acta Gastroenterol Belg ; 82(2): 267-272, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31314187

RESUMO

PURPOSE: In this study we aimed to compare and evaluate the efficacies of the low and high b value diffusion weighted imaging (DWI) sequences with three different T2-weighted (T2W) sequences. MATERIALS AND METHODS: 255 liver lesions of 147 patients who had undergone MR examinations of the upper abdomen were evaluated. A maximum number of 4 lesions was taken for consideration in patients with multiple lesions. Low and high b valued DWI and 3 different T2W sequences (SSFSE, FIESTA, and PROPELLER FSE) were utilized. The evaluations were done by 3 different radiologists, by utilizing the double blind principle. RESULTS: The lesion detection performances of the b 0 DWI, b 600 DWI, FIESTA T2W, SSFSE T2W, and PROPELLER FSE T2W sequences, were 95.7 %, 66.3 %, 94.4 %, 92.8 %, and 93.8 %, in sequence order. The high b value DWI sequence was able to detect malignant lesions with a higher accuracy rate than the T2W sequences. There was a moderate to high rate of agreement among the interpreters, and the lesion-detection rates of the interpreters were in line with their levels of expertise. CONCLUSION: Even though the higher lesion detection rates of the DWI sequences were not found to be statistically significant, it was concluded that making the evaluations with the addition of DWI to the imaging protocol would certainly decrease the lesion-missing rate, and it would be wise to utilize the DWI technique in routine liver MR imaging.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias Hepáticas/diagnóstico , Fígado/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Método Duplo-Cego , Humanos , Fígado/patologia
20.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(5): 501-506, 2019 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-31303612

RESUMO

OBJECTIVE: To investigate the feasibility and clinical application of intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI) technique in non-invasive assessment for early chronic allograft nephropathy (CAN).
 Methods: A total of 23 renal allograft recipients were recruited from inpatients or outpatients according to the inclusion and exclusion criteria for this study. Recipients were divided into a CAN group (n=12, pathologically confirmed early CAN patients) and a control group (n=11, volunteers with long-term stable renal function). Abdominal MRI was performed on patients of renal allograft with a multi-b value DWI sequence. IVIM2b-new software was used for obtaining the IVIM-DWI quantitative parameter pseudo-color maps and the values of IVIM-DWI of renal parenchyma, including the pure diffusion coefficient (D), perfusion correlation diffusion coefficient (D*) and perfusion fraction (f). The IVIM quantitative parameters between the two groups were compared using independent sample t test. ROC analysis was performed when the differences in parameter were statistically significant and the area under curve (AUC) was calculated.
 Results: In IVIM bi-exponential analysis, The D value was significantly decreased in the CAN group compared with the control group (P<0.05), whereas there are no significantly difference in value of D* and f between the two groups (all P>0.05). The AUC of D value for distinguishing the early CAN from the control were 0.784 with sensitivity and specificity at 58.3% and 90.9%, respectively.
 Conclusion: The IVIM-DWI quantitative parameter D can non-invasively assess early CAN to some extent. IVIM-DWI technique is expected to be an effective, easy and non-invasive method to detect early CAN, and assist early diagnose as well as dynamically monitor CAN.


Assuntos
Nefropatias/cirurgia , Transplante de Rim , Aloenxertos , Imagem de Difusão por Ressonância Magnética , Humanos , Imagem por Ressonância Magnética , Movimento (Física)
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