Motivation: The diagnostic performance of portable low-field-strength MRI (LF-MRI) is constrained by low spatial-resolution and signal-to-noise ratio. Goal(s): To evaluate the performance in detecting and quantifying ischemic lesions among SynthMRI, LF-MRI and real high-field-strength MRI (HF-MRI). Approach: We created a deep learning-based model to generate the synthetic super-resolution (3T) MRI (SynthMRI) based on LF-MRI (0.23T). We evaluated the performance in detecting and quantifying ischemic lesions among SynthMRI, LF-MRI and HF-MRI. Results: SynthMRI demonstrated high sensitivity in detecting the number and locations of ischemic lesions. Moreover, SynthMRI exhibited strong correlations with HF-MRI in the quantitative assessment of ischemic lesions, and significantly higher than portable LF-MRI. Impact: Synthetic super-resolution MRI images overcome the limitations of low spatial resolution and signal-to-noise ratio in portable low-field-strength MRI. It has the potential to replace high-field-strength MRI images in the neuroimaging of AIS, enabling portable low-field-strength MRI examinations with comparable performance.
Background and purpose To evaluate relationship between fluid-attenuated inversion recovery vascular hyperintensity (FVH) after intravenous thrombolysis and outcomes in different lesion patterns on diffusion-weighted imaging (DWI). Methods Patients with severe internal carotid or intracranial artery stenosis who received intravenous thrombolysis from March 2012 to April 2019 were analysed. They were divided into four groups by DWI lesion patterns: border-zone infarct (BZ group), multiple lesions infarct (ML group), large territory infarct (LT group), and single cortical or subcortical lesion infarct (SL group). Logistic regression was performed to identify risk factors for outcome (unfavourable outcome, modified Rankin Scale (mRS) ≥2; poor outcome, mRS ≥3). Results Finally, 203 participants (63.3±10.2 years old; BZ group, n=72; ML group, n=64; LT group, n=37; SL group, n=30) from 1190 patient cohorts were analysed. After adjusting for confounding factors, FVH (+) was associated with unfavourable outcome in total group (OR 3.02; 95% CI 1.49 to 6.13; p=0.002), BZ group (OR 4.22; 95% CI 1.25 to 14.25; p=0.021) and ML group (OR 5.44; 95% CI 1.41 to 20.92; p=0.014) patients. FVH (+) was associated with poor outcome in total group (OR 2.25; 95% CI 1.01 to 4.97; p=0.046), BZ group (OR 5.52; 95% CI 0.98 to 31.07; p=0.053) and ML group (OR 4.09; 95% CI 1.04 to 16.16; p=0.045) patients, which was marginal significance. FVH (+) was not associated with unfavourable or poor outcome in LT and SL groups. Conclusion This study suggests that association between FVH and outcome varies with different lesion patterns on DWI. The presence of FVH after intravenous thrombolysis may help to identify patients who require close observations in the hospitalisation in patients with border-zone and multiple lesion infarcts.
Objective To observe the effects of fasudil on levels of plasma MMP-2 and TGF-β1 in patients with chronic heart failure,and investigate the resistance mechanism of RHO kinase inhibitors in the process of ventricular remodeling.Methods Fourty patients with New York Heart Association (NYHA) NYHA Ⅳ were randomly divided into conventional treatment group and fasudil grou.Patients in conventional treatment group were given a formal anti-heart failure treatment according to the American heart failure guidelines,patients in fasudil group additionally received fasudil 60 mg dose intravenous drip qd for two weeks.The levels of plasma MMP-2,TGF-β1,LVEDD,LVEF were measured and compared before and after the treatment between the two groups.Results The MMP-2 and TGF-β1 plasma levels in the two groups decreased significantly after 2 weeks treatment (P ＜ 0.01),and fasudil treatment group was more obvious than conventional treatment group (P ＜ 0.05).Conclusions The patients with chronic heart failure with ventricular remodeled,heart contraction function droped,the MMP-2 and TGF-β1 expression levels increased,both may be involved in the heart failure of ventricular remodeling process.Fasudil can decrease MMP-2 and TGF-β1 expression levels,indicating that fasudil may play the role of ventricular remodeling in heart failure through this way.
Key words:
RHO kinase inhibitors; Heart failure ; Ventricular remodeling; Matrix metalloproteinases 2; Transformation growth factor-β1
Objective To observe the efficacy of oral sildenafil combined with intravenous levosimendan on patients with chronic heart failure and pulmonary hypertension.Methods From June 2012 to October 2012,18 patients with chronic congestive heart failure and pulmonary hypertension were randomised into control group and treatment group,with 15 cases in each group.In treatment group,on the basis of conventional treatment,patients were given an initial dose of levosimendan of 12 μg/kg,infused over 10 min,followed by a continuous infusion of 0.1 iμg/(kg · min) for 24 h,and oral seldenafil of 75 mg/d for 30 days.The patients in control group were given conventional treatment.NT-proBNP were tested before and after drug therapy,and LVEF and pulmonary artery pressure were measured by Vingmed vivid 7 Multifunctional color Doppler diagnostic instrument.Results In treatment group,LVEF increased higher than that in control group [(11.110 ±5.676)％ vs (2.700 ± 1.977)％],there was significant difference (t =3.981,P ＜ 0.01); NT-proBNP decreased more in treatment group than that in control group[(1844.730 ± 858.340) pg/ml vs (894.470 ± 890.371) pg/ml],there was significant difference (t =3.064,P ＜ 0.01) ; pulmonary artery pressure in treatment group decreased more than that in control group[(8.400 ± 11.344) mm Hg vs (3.600 ±3.291)mm Hg],there was significant difference (t =3.660,P ＜ 0.01).Conclusions Compared with conventional treatment,leosimendan combined with sildenafil could significantly reduce the pulmonary artery pressure and the NT-proBNP in patients with chronic heart failure and pulmonary hypertension,improve cardiac function,so it is effective.
Key words:
Levosimendan; Sildenafil; Chronic heart failure patients; Pulmonary hypertension
Arterial input function (AIF) is estimated from perfusion images as a basic curve for the following deconvolution process to calculate hemodynamic variables to evaluate vascular status of tissues. However, estimation of AIF is currently based on manual annotations with prior knowledge. We propose an automatic estimation of AIF in perfusion images based on a multi-stream 3D CNN, which combined spatial and temporal features together to estimate the AIF ROI. The model is trained by manual annotations. The proposed method was trained and tested with 100 cases of perfusion-weighted imaging. The result was evaluated by dice similarity coefficient, which reached 0.79. The trained model had a better performance than the traditional method. After segmentation of the AIF ROI, the AIF was calculated by the average of all voxels in the ROI. We compared the AIF result with the manual and traditional methods, and the parameters of further processing of AIF, such as time to the maximum of the tissue residue function (Tmax), relative cerebral blood flow, and mismatch volume, which are calculated in the Section Results. The result had a better performance, the average mismatch volume reached 93.32% of the manual method, while the other methods reached 85.04 and 83.04%. We have applied the method on the cloud platform, Estroke, and the local version of its software, NeuBrainCare, which can evaluate the volume of the ischemic penumbra, the volume of the infarct core, and the ratio of mismatch between perfusion and diffusion images to help make treatment decisions, when the mismatch ratio is abnormal.
Purpose: To investigate the relationships among the degree of intracranial atherosclerotic stenosis (ICAS), plaque enhancement (PE), and ischemic stroke events (ISEs) using 3.0T high-resolution magnetic resonance imaging (HR-MRI). Materials and Methods: Fifty-two ICAS patients who underwent HR-MRI were retrospectively analysed. The patients were divided into two groups according to the results of whole-brain digital subtraction angiography (DSA): the mild-moderate stenosis group (group MID) and the severe stenosis group (group SEV). According to the onset time of the ISEs, the plaques were divided into the acute/sub-acute phase culprit plaque group (group ACU, within one month), the chronic-phase culprit plaque group (group CHR, more than one month), and the nonculprit plaque group (group NON). Two neuroradiologists independently measured the signal intensity of PE and pituitary enhancement in the HR-MRI and calculated the radio of the two indices. According to the ratio, the patients were divided into 3 groups: the marked enhancement group (group MA), the mild enhancement group (group ME), and the no enhancement plaque group (group NO). The relationships among the degree of ICAS, the degree of PE and ISEs were analysed. Results: Seventy-two ICAS plaques were identified in 52 patients. The multiple independent samples Kruskal-Wallis H test showed that the differences among group ACU, CHR, and NON were significant in the degree of PE (P=0.002). Group CHR and group NON were combined as the non-acute phase group (group non-ACU). Group NO and group ME were combined as the non-marked enhancement group (gruop non-MA). The comparison between group ACU and group non-ACU showed significant differences in the degree of both ICAS (P=0.014) and PE (P=0.006) according to the univariate logistic regression. The multivariate logistic regression model was used to analyse the impact of the degree of ICAS and PE on ISEs, and the results showed that severe stenosis (P=0.036) and marked PE (P=0.013) were independent risk factors for acute ISEs, respectively. Conclusion: Severe intracranial arterial stenosis and marked plaque enhancement are independent risk factors for acute ischemic stroke events, respectively. The study provides new ideas for further exploring the pathogenesis of stroke caused by intracranial atherosclerotic stenosis.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)