颅脑MRI/CT中环行强化病灶的鉴别诊断

＂同病异影、同影异病＂是临床影像诊断医生在日常工作中常常遇到的问题,也是诊断工作中的难点。文章就脑实质内较为常见的、具有环形强化特点病变的MRI/CT影像学表现及其鉴别诊断进行综合分析。     

The neuropathology of developmental dysphasia: Behavioral,morphological, and physiological evidence for a pervasive temporal processing disorder

Over the past twenty years, Tallal and colleagues have directed their research toward defining the neuropathological mechanisms responsible for developmental dysphasia. We have hypothesized that higher level auditory processing dysfunction, which has previously been associated with developmental dysphasia, may result from more basic temporal processing deficits which interfere with the resolution of rapidly presented, brief duration stimuli. This temporal processing deficit interferes with adequate perception of specific verbal stimuli which require resolution of brief duration formant transitions, resulting in disordered language development. The temporal processing deficit occurs across multiple sensory modalities, and also affects rapid and sequential motor production skills. Despite relatively normal clinical neuroradiological examinations, in vivo morphological analysis, utilizing magnetic resonance imaging techniques for quantitative volumetric measurements of specific brain structures, has identified abnormalities in superior parietal, prefrontal, and temporal cortices, as well as diencephalic and caudate nuclei. Abnormalities in structures which are involved in multimodal processing and sensory motor integration is consistent with the behavioral profile of developmental dysphasia. Two alternative hypotheses regarding the neurophysiological basis of the multimodal temporal processing disorder include: dysfunction in specific cellular systems which subserve rapid, transient processing; and abnormal gating of sensory relay by intralaminar and reticular thalamic nuclei.     

神经伦理学——人文科学与神经科学的完美结合体

神经科学在社会发展中起着越来越重要的作用,由于它的飞速发展也带来了一系列伦理和法律方面的问题。神经伦理学是生物伦理和神经科学交叉的新领域,它建立在精神与行为关系的基础之上。从广义而言,神经伦理学是研究与神经科学有关的伦理、法律和社会政策影响的一门学科。本文综述了神经伦理学的主要研究领域,以及各个研究方向。     

磁共振成像仿真平台设计与实现

为了更好地研究MRI成像技术和图像重建算法,采用Matlab图形用户界面创建了MRI仿真平台。该平台模拟了线性、螺旋及并行扫描3种成像方式,可以导入不同模型图像,设计K空间扫描轨迹,模拟K空间数据采集过程,显示采集信号的波形。对这3种成像方式的图像重建加以实现,并对重建误差进行了分析。该平台为其它各种MRI数据采集和图像重建新算法的研究提供了一种有效工具。     

3D brain glioma segmentation in MRI through integrating multiple densely connected 2D convolutional neural networks

To overcome the computational burden of processing three-dimensional(3 D) medical scans and the lack of spatial information in two-dimensional(2 D) medical scans, a novel segmentation method was proposed that integrates the segmentation results of three densely connected 2 D convolutional neural networks(2 D-CNNs). In order to combine the lowlevel features and high-level features, we added densely connected blocks in the network structure design so that the low-level features will not be missed as the network layer increases during the learning process. Further, in order to resolve the problems of the blurred boundary of the glioma edema area, we superimposed and fused the T2-weighted fluid-attenuated inversion recovery(FLAIR) modal image and the T2-weighted(T2) modal image to enhance the edema section. For the loss function of network training, we improved the cross-entropy loss function to effectively avoid network over-fitting. On the Multimodal Brain Tumor Image Segmentation Challenge(BraTS) datasets, our method achieves dice similarity coefficient values of 0.84,0.82, and 0.83 on the BraTS2018 training; 0.82, 0.85, and 0.83 on the BraTS2018 validation; and 0.81, 0.78, and 0.83 on the BraTS2013 testing in terms of whole tumors, tumor cores, and enhancing cores, respectively. Experimental results showed that the proposed method achieved promising accuracy and fast processing, demonstrating good potential for clinical medicine.