Reduced Imaging Time and Improved Image Quality of 3D Isotropic T2-Weighted Magnetic Resonance Imaging with Compressed Sensing for the Female Pelvis

This study is to compare three-dimensional(3D)isotropic T2-weighted magnetic resonance imaging(MRI)with compressed sensing-sampling perfection with application optimized contrast(CS-SPACE)and the conventional image(3D-SPACE)sequence in terms of image quality,estimated signal-to-noise ratio(SNR),relative contrast-to-noise ratio(CNR),and the lesions’conspicuous of the female pelvis.Thirty-six females(age:51,28-73)with cervical carcinoma(n=20),rectal carcinoma(n=7),or uterine fibroid(n=9)were included.Patients underwent magnetic resonance(MR)imaging at a 3T scanner with the sequences of 3D-SPACE,CS-SPACE,and twodimensional(2D)T2-weighted turbo-spin echo(TSE).Quantitative analyses of estimated SNR and relative CNR between tumors and other tissues,image quality,and tissue conspicuity were performed.Two radiologists assessed the difference in diagnostic findings for carcinoma.Quantitative values and qualitative scores were analyzed,respectively.The estimated SNR and the relative CNR of tumor-to-muscle obturator internus,tumor-to-myometrium,and myometrium-to-muscle obturator internus was comparable between 3D-SPACE and CS-SPACE.The overall image quality and the conspicuity of the lesion scores of the CS-SPACE were higher than that of the 3D-SPACE(P<0.01).The CS-SPACE sequence offers shorter scan time,fewer artifacts,and comparable SNR and CNR to conventional 3D-SPACE,and has the potential to improve the performance of T2-weighted images.

Comment on: “Development of a CLDN18.2-targeting immuno-PET probe for non-invasive imaging in gastrointestinal tumors”

In the ever-evolving landscape of cancer research and treatment,the quest for novel and non-invasive imaging techniques has become crucial for accurate diagnosis and effective therapy.This study[1]successfully developed a good manufacturing practices(GMP)grade ^(89)Zr-labeled anti-Claudin18.2(CLDN18.2)recombinant humanized antibody TST001.^(89)Zr-DFO-TST001 exhibited high radiochemical purity(>99%)and specific activity(24.15±1.34 GBq/mmol).It demonstrated good specificity and rapid tumor accumulation in vivo and in vivo.Through immuno-PET imaging,it enables non-invasive visualization and quantification of CLDN18.2 expression level in CLDN18.2-positive gastrointestinal tumor models.

Perfusion magnetic resonance imaging of the liver

Perfusion magnetic resonance imaging (MRI) studies quantify the microcirculatory status of liver parenchyma and liver lesions, and can be used for the detection of liver metastases, assessing the effectiveness of antiangiogenic therapy, evaluating tumor viability after anticancer therapy or ablation, and diagnosis of liver cirrhosis and its severity. In this review, we discuss the basic concepts of perfusion MRI using tracer kinetic modeling, the common kinetic models applied for analyses, the MR scanning techniques, methods of data processing, and evidence that supports its use from published clinical and research studies. Technical standardization and further studies will help to establish and validate perfusion MRI as a clinical imaging modality.

What can imaging tell us about cognitive impairment and dementia?

Dementia is a contemporary global health issue with far reaching consequences, not only for affected individuals and their families, but for national and global socioeconomic conditions. The hallmark feature of dementia is that of irreversible cognitive decline, usually affecting memory, and impaired activities of daily living. Advances in healthcare worldwide have facilitated longer life spans, increasing the risks of developing cognitive decline and dementia in late life. Dementia remains a clinical diagnosis. The role of structural and molecular neuroimaging in patients with dementia is primarily supportive role rather than diagnostic, American and European guidelines recommending imaging to exclude treatable causes of dementia, such as tumor, hydrocephalus or intracranial haemorrhage, but also to distinguish between different dementia subtypes, the commonest of which is Alzheimer's disease. However, this depends on the availability of these imaging techniques at individual centres. Advanced magnetic resonance imaging(MRI) techniques, such as functional connectivity MRI, diffusion tensor imaging and magnetic resonance spectroscopy, and molecular imaging techniques, such as 18 F fluoro-deoxy glucose positron emission tomography(PET), amyloid PET, tau PET, are currently within the realm of dementia research but are available for clinical use. Increasingly the research focus is on earlier identification of at risk preclinical individuals, for example due to family history. Intervention at the preclinical stages before irreversible brain damage occurs is currently the best hope of reducing the impact of dementia.

Modern imaging of the tracheo-bronchial tree

Recent state-of-the-art computed tomography and improved three-dimensional(3-D) postprocessing techniques have revolutionized the capability of visualizing airway pathology,offering physicians an advanced view of pathology and allowing for appropriate management planning.This article is a comprehensive review of trachea and main bronchi imaging,with emphasis on the dynamic airway anatomy,and a discussion of a wide variety of diseases including,but not limited to,congenital large airway abnormalities,tracheobronchial stenoses,benign and malignant neoplasms and tracheobronchomalacia.The importance of multiplanar reconstruction,3-D reconstruction and incorporation of dynamic imaging for non-invasive evaluation of the large airways is stressed.

Diagnosis of focal liver lesions with deep learning-based multichannel analysis of hepatocyte-specific contrast-enhanced magnetic resonance imaging

BACKGROUND The nature of input data is an essential factor when training neural networks.Research concerning magnetic resonance imaging(MRI)-based diagnosis of liver tumors using deep learning has been rapidly advancing.Still,evidence to support the utilization of multi-dimensional and multi-parametric image data is lacking.Due to higher information content,three-dimensional input should presumably result in higher classification precision.Also,the differentiation between focal liver lesions(FLLs)can only be plausible with simultaneous analysis of multisequence MRI images.AIM To compare diagnostic efficiency of two-dimensional(2D)and three-dimensional(3D)-densely connected convolutional neural networks(DenseNet)for FLLs on multi-sequence MRI.METHODS We retrospectively collected T2-weighted,gadoxetate disodium-enhanced arterial phase,portal venous phase,and hepatobiliary phase MRI scans from patients with focal nodular hyperplasia(FNH),hepatocellular carcinomas(HCC)or liver metastases(MET).Our search identified 71 FNH,69 HCC and 76 MET.After volume registration,the same three most representative axial slices from all sequences were combined into four-channel images to train the 2D-DenseNet264 network.Identical bounding boxes were selected on all scans and stacked into 4D volumes to train the 3D-DenseNet264 model.The test set consisted of 10-10-10 tumors.The performance of the models was compared using area under the receiver operating characteristic curve(AUROC),specificity,sensitivity,positive predictive values(PPV),negative predictive values(NPV),and f1 scores.RESULTS The average AUC value of the 2D model(0.98)was slightly higher than that of the 3D model(0.94).Mean PPV,sensitivity,NPV,specificity and f1 scores(0.94,0.93,0.97,0.97,and 0.93)of the 2D model were also superior to metrics of the 3D model(0.84,0.83,0.92,0.92,and 0.83).The classification metrics of FNH were 0.91,1.00,1.00,0.95,and 0.95 using the 2D and 0.90,0.90,0.95,0.95,and 0.90 using the 3D models.The 2D and 3D networks'performance in the diagnosis of HCC were 1.00,0.80,0.91,1.00,and 0.89 and 0.88,0.70,0.86,0.95,and 0.78,respectively;while the evaluation of MET lesions resulted in 0.91,1.00,1.00,0.95,and 0.95 and 0.75,0.90,0.94,0.85,and 0.82 using the 2D and 3D networks,respectively.CONCLUSION Both 2D and 3D-DenseNets can differentiate FNH,HCC and MET with good accuracy when trained on hepatocyte-specific contrast-enhanced multi-sequence MRI volumes.

How random is the random forest ? Random forest algorithm on the service of structural imaging biomarkers for Alzheimer's disease: from Alzheimer's disease neuroimaging initiative(ADNI) database

Neuroinformatics is a fascinating research field that applies computational models and analytical tools to high dimensional experimental neuroscience data for a better understanding of how the brain functions or dysfunctions in brain diseases. Neuroinformaticians work in the intersection of neuroscience and informatics supporting the integration of various sub-disciplines（behavioural neuroscience, genetics, cognitive psychology, etc.） working on brain research. Neuroinformaticians are the pathway of information exchange between informaticians and clinicians for a better understanding of the outcome of computational models and the clinical interpretation of the analysis. Machine learning is one of the most significant computational developments in the last decade giving tools to neuroinformaticians and finally to radiologists and clinicians for an automatic and early diagnosis-prognosis of a brain disease. Random forest（RF） algorithm has been successfully applied to high-dimensional neuroimaging data for feature reduction and also has been applied to classify the clinical label of a subject using single or multi-modal neuroimaging datasets. Our aim was to review the studies where RF was applied to correctly predict the Alzheimer＇s disease（AD）, the conversion from mild cognitive impairment（MCI） and its robustness to overfitting, outliers and handling of non-linear data. Finally, we described our RF-based model that gave us the 1 ^（st） position in an international challenge for automated prediction of MCI from MRI data.

Clinical applications of feature-tracking cardiac magnetic resonance imaging

Cardiovascular diseases represent the leading cause of mortality and morbidity in the western world. Assessment of cardiac function is pivotal for early diag-nosis of primitive myocardial disorders, identification of cardiac involvement in systemic diseases, detection of drug-related cardiac toxicity as well as risk stratification and monitor of treatment effects in patients with heart failure of various etiology. Determination of ejection fraction with different imaging modalities currently represents the gold standard for evaluation of cardiac function. However, in the last few years, cardiovascular magnetic resonance feature tracking techniques has emerged as a more accurate tool for quantitative evalu-ation of cardiovascular function with several parameters including strain, strain-rate, torsion and mechanical dispersion. This imaging modality allows precise quantification of ventricular and atrial mechanics by directly evaluating myocardial fiber deformation. The purpose of this article is to review the basic principles, current clinical applications and future perspectives of cardiovascular magnetic resonance myocardial feature tracking, highlighting its prognostic implications.

Role of molecular imaging in the management of patients affected by inflammatory bowel disease:State-of-the-art

AIM To present the current state-of-the art of molecular imaging in the management of patients affected by inflammatory bowel disease(IBD).METHODS A systematic review of the literature was performed in order to find important original articles on the role of molecular imaging in the management of patients affected by IBD. The search was updated until February 2016 and limited to articles in English.RESULTS Fifty-five original articles were included in this review, highlighting the role of single photon emission tomography and positron emission tomography. CONCLUSION To date, molecular imaging represents a useful tool to detect active disease in IBD. However, the available data need to be validated in prospective multicenter studies on larger patient samples.

Magnetic resonance imaging biomarkers of gastrointestinal motor function and fluid distribution

Magnetic resonance imaging(MRI) is a well established technique that has revolutionized diagnostic radiology. Until recently, the impact that MRI has had in the assessment of gastrointestinal motor function and bowel fluid distribution in health and in disease has been more limited, despite the novel insights that MRI can provide along the entire gastrointestinal tract. MRI biomarkers include intestinal motility indices, small bowel water content and whole gut transit time. The present review discusses new developments and applications of MRI in the upper gastrointestinal tract, the small bowel and the colon reported in the literature in the last 5 years.

Complex Cystic Breast Masses: An Ultrasound Imaging Review

Cystic lesions are very commonly encountered entities in the breast. Among these, Complex Cystic Breast Masses (CCBMs), which contain both anechoic and echogenic components, can result in a variety of imaging appearances. These include cystic lesions with thick walls and/or internal septa, intracystic nodular lesions, and solid-cystic masses of varying compositions. Ultrasound is the mainstay for evaluating cystic lesions, and thus recognizing the imaging features appropriately and suggesting suitable interventional procedures are included in their management. In this pictorial essay, we describe the wide range of ultrasound appearances of CCBMs with a number of clinically encountered examples from our institution. This article would enhance the understanding of readers in possible differentials to be included in their clinical practice and to suggest appropriate further intervention, when deemed necessary.

Ectopic Pelvic Leiomyoma and Diagnostic Difficulty in Imaging: A Case Report from Conakry, Guinea

Introduction: Fibromyomas are benign tumours of frequent uterine location, most often found in black women, whose diagnosis of certainty is histological. The extra uterine location is rare and the physio-pathogenesis is poorly understood. This location poses diagnostic problems on imaging. Management is based on tumour resection. Observation: The authors report a clinical case of a 31-year-old woman who was seen for non-febrile hypogastric pain with a large abdominopelvic mass on physical examination. There was no particular history. The biology did not show any abnormality. Ultrasound with Doppler found a mass that was difficult to characterize, and was completed by a CT scan and a pelvic MRI. The management was surgical with an evolution marked by complications. Conclusion: Ectopic leiomyoma is a rare condition. This location poses diagnostic problems on imaging. Management depends on the type of extra uterine presentation of the myoma.

Contribution of Medical Imaging in the Diagnosis of Urinary Disorders in Children at the Charles de Gaulle University Hospital in Ouagadougou

Purpose: The purpose of our study, which focused on the contribution of medical imaging in the diagnosis of urinary tract diseases in children at the Charles de Gaulle University Hospital of Ouagadougou, was to study the role of medical imaging in the diagnosis of urinary tract diseases in patients aged 15 years or less at the CHUP-CDG. Patients and Methods: This was a descriptive cross-sectional study with the retrospective collection covering the period from January 1, 2009 to December 31, 2018, i.e., 10 years. We collected a total of 833 medical imaging examinations, performed in 735 patients. The mean age of the patients was 40 months, infants accounted for 37.69% of the cases. Male patients were more numerous with a sex ratio of 1.53. Results: Ultrasonography was performed in 652 patients or 78.27%, ASP RX in 128 patients or 10.88%. URC and UIV were used in 6.53% and 0.68% of patients, respectively. CT and MRI were not performed in our study. The most frequent clinical urinary signs were dysuria (58.13%) and hematuria (43.94%). Ultrasonography was the most requested examination (78.27%), followed by conventional radiography (15.37%). Urinary lithiasis was by far the most common urinary condition (46.86%), followed by urinary tract infections (32.19%) and malformative uropathies (14.93%), of which the posterior urethral valve was the most frequent. Imaging was also used to find other conditions associated with urinary tract diseases. Conclusion: Medical imaging plays a major role in the diagnosis and management of urinary tract diseases in children. It has limitations, that is why a formal meeting between clinicians and radiologists is necessary for a better choice of imaging techniques and efficient management of these conditions.

Imaging of Insulitis in NOD Mice with IL-2-Gd-DTPA and 1.5 T MRI

To explore the possibility to use 1.5 T MRI in imaging of accumulating gadolinium (Gd) into inflamed en- docrine pancreas (insulitis), we compared intravenously delivered IL-2-Gd-DTPA and Gd-DTPA (Magne- vist?) in phenotypically healthy 12 weeks old female non-obese diabetic (NOD) mice. At 1 to 48 h after the injection mice were sacrificed and the pancreas-to-background ratio was determined using MRI. In addition Gd concentration of the pancreas and plasma were measured. The pancreas-to-plasma ratio of Gd was 25-fold 24 h after the i.v. injection of IL-2-Gd-DTPA. At the same time the pancreas-to-background ratio measured with 1.5T MRI was 1.5-times higher in the NOD mice receiving IL-2-Gd-DTPA than Magnevist? (271 ± 37 vs. 183 ± 0,1, P = 0.04) indicating that sufficient differences may exist between IL-2-Gd-DTPA accumulating in the pancreas and in the surrounding tissues to support the use of MRI for imaging of pan- creatic insulitis.

Anti-inflammatory effects of Solanum procumbens on a low dose complete Freund's adjuvant-induced arthritis rat model

Objective:To investigate the anti-inflammatory and analgesic effects of Solanum procumbens on complete Freund’s adjuvantinduced arthritis rat models.Methods:We isolated and identified five compounds in the ethanolsoluble Solanum procumbens extract(SP)with anti-inflammatory effects,including ursolic acid,β-sitosterol,hexadecanoic acid,cisvaccenic acid,and vanillic acid.Additionally,we investigated the anti-inflammatory effects of SP on rheumatoid arthritis symptoms,including paw volumes,local temperatures,withdrawal latency,and mechanical withdrawal threshold at the hind paw and white blood cell(WBC)number from complete Freund’s adjuvant-induced arthritis rat models.Results:We have successfully established a complete Freund’s adjuvant-induced arthritis rat model at a low dose(1 mg/mL).SP extract significantly reduced paw volumes(P<0.05),prolonged withdrawal latencies(P<0.05),decreased local temperature,and increased the mechanical withdrawal threshold(P<0.05),but only SP extract at the dose of 300 mg/kg significantly decreased WBC numbers.Conclusions:SP extract could be a potential medication candidate with anti-inflammatory effects for arthritis,but it requires further investigation into the mechanism of the SP and its effectiveness on other models as well as clinical trials.

同相位和反相位MR成像快速评价非酒精性脂肪肝的脂肪含量

目的 以^1H-MRS作为参考标准，评价同相位和反相位MR成像在估测非酒精性脂肪肝（NAFLD）病人的肝脏脂肪含量（LFC）中的价值。方法 所有受检者均签署知情同意书，当地伦理委员会也同意开展此项前瞻性研究计划。共有33例NAFLD高风险的2型糖尿病病人[男性23例，女性10例；平均年龄（62．8±8．3）岁，范围48～77岁]接受了1．5T MRI的肝脏^1H-MRS检查及同相位和反相位MRI检查。

Coronary computed tomography angiography in coronary artery disease

AIM: To investigate the research directions of coronary computed tomography (CT) angiography in the diagnosis of coronary artery disease (CAD) based on a systematic review of the literature.METHODS: A search of articles on coronary CT angiography in the diagnosis of CAD was performed during a 6-year-period between 2005 and 2010 from f ive main radiology journals namely, Radiology, American Journal of Roentgenology, European Radiology, European Journal of Radiology and British Journal of Radiology. Analysis of the references was focused on the research directions of coronary CT angiography with regard to the type of studies in terms of diagnostic value, application of dose-reduction strategies and resultant effective radiation doses with use of these techniques.RESULTS: One hundred and forty two studies were identified which met the selection criteria and were included in the analysis. 64-slice CT (single source anddual-source CT) dominated 78% of the coronary CT angiography studies. Prior to 2007, research was focused on the diagnostic value of coronary CT angiography, but since 2008 more attention has been paid to radiation dose reduction. Radiation dose was reported in 64 studies, representing 45% of total studies published in the f ive radiology journals. Various dose-saving strategies have been implemented and prospective electrocardiography-triggering and high pitch techniques were found to be the most effective approaches for radiation dose reduction, with the corresponding mean effective dose being 3.5 ± 1.9 mSv and 1.7 ± 0.6 mSv, respectively.CONCLUSION: This review shows that the current research in coronary CT angiography has shifted from the previous focus on diagnostic accuracy in CAD to more emphasis on radiation dose reduction.

第 7 肺癌症 TNM 分类和阶段系统: 变化和含意的评论

Lung cancer is the most common cause of death from cancer in males,accounting for more than 1.4 million deaths in 2008.It is a growing concern in China,Asia and Africa as well.Accurate staging of the disease is an important part of the management as it provides estimation of patient’s prognosis and identifies treatment sterategies.It also helps to build a database for future staging projects.A major revision of lung cancer staging has been announced with effect from January 2010.The new classification is based on a larger surgical and non-surgical cohort of patients,and thus more accurate in terms of outcome prediction compared to the previous classification.There are several original papers regarding this new classification which give comprehensive description of the methodology,the changes in the staging and the statistical analysis.This overview is a simplified description of the changes in the new classification and their potential impact on patients’ treatment and prognosis.

综合多种预测方案实现遮挡情况下的目标跟踪(英文)

由于采用了多种运动预测方案 ,本文提出的目标跟踪方法能选择最佳的观测结果 ,实现对非标定固定焦距的静止摄像机的单目图像序列中的目标跟踪 .静态背景参考图像由混合模型法估计 ,在最简单的环境下 ,跟踪算法则采用匀加速运动模型对目标完成跟踪 .本文主要贡献是采用了三个预测器和最小方差相关时选择目标最可能的位置 .三个预测器分别是 :α - β跟踪方案、卡尔曼滤波和区域分割匹配方案 .

Tuberculous abscess in hepatoduodenal ligament: Evaluation with contrast-enhanced computed tomography

Two patients with tuberculous abscess in the hepatoduodenal ligament were studied. Both patients underwent contrast-enhanced computed tomography (CT) scan. The abscess showed a low density with an irregular thick wall in the hepatoduodenal ligament on CT images, the margin was poorly defined. Contrastenhanced CT images showed the contrast-enhanced thick wall, homogeneous and peripheral-enhanced lymph nodes. Although features of the tuberculous abscess in the hepatoduodenal ligament could be conspicuously shown with contrast-enhanced CT, further experience is needed to evaluate the potential value of CT in detecting early tuberculous abscess in relation to other entities in the hepatoduodenal ligament.