Susceptibility weighted imaging in the evaluation of hemorrhagic diffuse axonal injury

Diffuse axonal injury（DAI）is axonal and small vessel injury produced by a sudden acceleration of the head by an external force,and is a major cause of death and severe disability（Paterakis et al.,2000）.Prognosis is poorer in patients with apparent hemorrhage than in those without（Paterakis et al.,2000）.Therefore,it is important to identify the presence and precise position of hemorrhagic foci for a more accurate diagnosis.CT and magnetic resonance imaging（MRI）have long been applied in the diagnosis of DAI, but they are not sensitive enough for the detection of small hemorrhagic foci, and cannot meet the requirements for early diagnosis. A major advance in MRI has been the development of susceptibility weighted imaging （SWI）, which has greatly increased the ability to detect small hemorrhagic foci after DAI （Ashwal et al., 2006）.

Susceptibility-weighted imaging is suitable for evaluating signal strength in different brain regions of a rabbit model of acute hemorrhagic anemia

Acute hemorrhagic anemia can decrease blood flow and oxygen supply to brain, and affect its physiological function. While detecting changes in brain function in patients with acute hemorrhagic anemia is helpful for preventing neurological complications and evaluating therapeutic effects, clinical changes in the nervous systems of these patients have not received much attention. In part, this is because current techniques can only indirectly detect changes in brain function following onset of anemia, which leads to lags between real changes in brain function and their detection.

A Study of Different Unwarping Methods for Omnidirectional Imaging

Omni-directional imaging system is becoming more and more common in reducing the maintenance fees and the number of cameras used as well as increasing the angle of view in a single camera. Due to omni-directional images are not directly understandable, an approach namely the un-warping process, has been implemented in converting the omni-directional image to a panoramic image, making it understandable. There are different kinds of methods used for the implementation of this approach. This paper evaluates the performance of the 3 universal un-warping methods currently applied actively around the world in transforming omni-directional image to panoramic image, namely the pano-mapping table method, discrete geometry method （DGT） and the log-polar mapping method. The algorithm of these methods will first be proposed, and the code will then be generated and be tested on several different omni-directional images. The images converted will then be compared among each other and be evaluated based on their performance on the resolutions, quality, algorithm used, complexity based on Big-O computations, processing time, and finally their data compression rate available for each of the methods. The most preferable un-warping method will then be concluded, taking into considerations all these factors.

Coronary arterial bypass graft patency evaluated by multi-detector computed tomography and magnetic resonance imaging

The progression of atherosclerosis of the coronary artery does not stop after coronary arterial bypass grafting (CABG) surgery.……

PANCREATO-BILIARY TUMOR: MR DIAGNOSIS AND RESECTABILITY ASSESSMENT

Objective: TO evaluate the clinical value of MR multi-imaging technique in diagnosing and assessing the resectability of pancreato-biliary tumor. Methods The prospective diagnosis and resectability of 17 patients with suspicious pancreato-biliary tumors were evaluated. Surgical findings and pathologic results confirmed pancreatic adenocarcinoma in 11 cases, cholangiocarcinoma in 4, and non-neoplastic lesion in 2. MR multi-imaging protocol, including MR cross-sectional imaging, us cholangiopancreatography (MRCP ), and three-dimensional dynamic contrast-enhanced MR portography (3D DCE MRP), were performed in all patients. Results MR multi-imaging technique allowed-correct diagnosing 15 of 17 (88. 2% ) patients with pancreato-biliary tumors. The accuracy in detecting the range of tumor invasion was 64. 4%. The sensitivity, speificity, accuracy, positive, and negative predictive value of MR multi-imaging technique in assessing the resectability of pancreato-biliary tumors were 83. 3%, 77. 8%, 80. 0%, 71. 4%, and 87. 5%, respectively. Conclusion MR multi-imaging technique can not only improve the diagnostic ability of pancreato-biliary tumor, but also assess the surgical reartability of the tumor. With the fast development of MR techniques, the diagnosing and pre-operative assessment of aoncreato-biliary tumor may be more simplified and efficient by using the non-invasive "all-in-one" method.

Objective Image Fusion Quality Evaluation Using Structural Similarity

Objective evaluations of fused images are important in comparing the performance of different image fusion algorithms. This paper describes a structural similarity metric that does not use a reference image for image fusion evaluations. The metric is based on the universal image quality index and addresses not only the similarities between the input images and the fused image, but also the similarities among the input images. The evaluation process distinguishes between complementary information and redundant information using similarities among the input images. The metric uses the information classification to estimate how much structural similarity is preserved in the fused image. Tests demonstrate that the metric correlates well with subjective evaluations of the fused images.

Performance assessment of Cs I(T1) screens on various substrates for X-ray imaging

Thallium-doped cesium iodide（Cs I（Tl）） screens are widely used in X-ray imaging devices because of the columnar structure of the Cs I（Tl） layer, but few reports focus on the optical role of the substrate in the screen system.In this paper, four substrates including fused silica（Si O2）, silver-film coated Si O2, graphite（C） and fiber optic plate（FOP） are used to fabricate Cs I（Tl） screens by thermal evaporation. Their imaging performance is evaluated by relative light output（RLO）, modulation transfer function（MTF）, normalized noise power spectrum（NNPS） and noise equivalent quanta（NEQ）. The results reveal that although Cs I（Tl） film on graphite plate yields images with the lowest light output, it presents relatively higher spatial resolution and better signal-to-noise characteristics.However, films on Si O2 plate obtain low MTF but high NNPS curves, whether they are coated with silver film or not.Furthermore, scintillation screens on FOP have bright images with low NNPS and high NEQ, but have the lowest MTF. By controlling the substrate optical features, Cs I（Tl） films can be tailored to suit a given application.

Deep image synthesis from intuitive user input:A review and perspectives

In many applications of computer graphics,art,and design,it is desirable for a user to provide intuitive non-image input,such as text,sketch,stroke,graph,or layout,and have a computer system automatically generate photo-realistic images according to that input.While classically,works that allow such automatic image content generation have followed a framework of image retrieval and composition,recent advances in deep generative models such as generative adversarial networks(GANs),variational autoencoders(VAEs),and flow-based methods have enabled more powerful and versatile image generation approaches.This paper reviews recent works for image synthesis given intuitive user input,covering advances in input versatility,image generation methodology,benchmark datasets,and evaluation metrics.This motivates new perspectives on input representation and interactivity,cross fertilization between major image generation paradigms,and evaluation and comparison of generation methods.

Versus—A tool for evaluating visualizations and image quality using a 2AFC methodology

Novel visualization methods and strategies are necessary to cope with the deluge of datasets present in any scientific field to make discoveries and find answers to previously unanswered questions.These methods and strategies should not only present scientific findings as images in a concise way but also need to be effective and expressive,which often remain untested.Here,we present Versus,a tool to enable easy image quality assessment and image ranking,utilizing a two-alternative forced choice methodology(2AFC)and an efficient ranking algorithm based on a binary search.The tool provides a systematic way of setting up evaluation experiments via the web without the necessity to install any additional software or require any programming skills.Furthermore,Versus can easily interface with crowdsourcing platforms,such as Amazon’s Mechanical Turk,or can be used as a stand-alone system to carry out evaluations with experts.We demonstrate the use of Versus by means of an image evaluation study,aiming to determine if hue,saturation,brightness,and texture are good indicators of uncertainty in three-dimensional protein structures.Drawing from the power of crowdsourcing,we argue that there is demand and also great potential for this tool to become a standard for simple and fast image evaluations,with the aim to test the effectiveness and expressiveness of scientific visualizations.