scholarly journals New Strategies in the Design of Paramagnetic CAs

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Alessio Smeraldo ◽  
Paolo A. Netti ◽  
Enza Torino
Keyword(s):  
Imaging Modality ◽  
Critical Evaluation ◽  
Physical Principle ◽  
Characteristic Relaxation Time ◽  
Magnetic Resonance Imaging Mri ◽  
Elimination Pathway ◽  
Anatomical Information ◽  
Clinical Mri ◽  
New Strategies

Nowadays, magnetic resonance imaging (MRI) is the first diagnostic imaging modality for numerous indications able to provide anatomical information with high spatial resolution through the use of magnetic fields and gradients. Indeed, thanks to the characteristic relaxation time of each tissue, it is possible to distinguish between healthy and pathological ones. However, the need to have brighter images to increase differences and catch important diagnostic details has led to the use of contrast agents (CAs). Among them, Gadolinium-based CAs (Gd-CAs) are routinely used in clinical MRI practice. During these last years, FDA highlighted many risks related to the use of Gd-CAs such as nephrotoxicity, heavy allergic effects, and, recently, about the deposition within the brain. These alerts opened a debate about the opportunity to formulate Gd-CAs in a different way but also to the use of alternative and safer compounds to be administered, such as manganese- (Mn-) based agents. In this review, the physical principle behind the role of relaxivity and the T1 boosting will be described in terms of characteristic correlation times and inner and outer spheres. Then, the recent advances in the entrapment of Gd-CAs within nanostructures will be analyzed in terms of relaxivity boosting obtained without the chemical modification of CAs as approved in the chemical practice. Finally, a critical evaluation of the use of manganese-based CAs will be illustrated as an alternative ion to Gd due to its excellent properties and endogenous elimination pathway.

scholarly journals Endoscopic Ultrasound for Detection of Liver Metastasis: Hope or Hype?

2021 ◽  
Author(s):  
Anupam Kumar Singh ◽  
Surinder S. Rana
Keyword(s):  
Endoscopic Ultrasound ◽  
Imaging Modality ◽  
Intraoperative Ultrasound ◽  
Liver Lesions ◽  
Contrast Enhanced ◽  
Magnetic Resonance Imaging Mri ◽  
Hepatic Lesions ◽  
Enhanced Computed Tomography ◽  
Metastatic Liver

AbstractTransabdominal ultrasonography, contrast-enhanced computed tomography, and magnetic resonance imaging (MRI) are the common diagnostic tests for the detection of hepatic lesions. Use of enhanced and advanced MRI technique, that is, diffusion weighted MRI and hepatocyte-specific contrast agents, has further improved the accuracy of detection of metastatic liver lesions ≤10 mm in diameter. However, even with these advanced imaging modalities sensitivity is low for lesions smaller than 10 mm when compared with standard intraoperative ultrasound. Endoscopic ultrasound (EUS) is an emerging imaging modality with resolution sufficient to detect and sample lesions as small as 5 mm in diameter. In this news and views, we have discussed the role of standard and enhanced EUS for the detection of metastatic liver lesions.

THE ROLE OF INTERVENTIONAL RADIOLOGY IN OBSTETRICS

2004 ◽  
Vol 15 (2) ◽  
pp. 145-180 ◽  
Author(s):  
JOHN R KACHURA
Keyword(s):  
Interventional Radiology ◽  
Imaging Modality ◽  
Surgical Techniques ◽  
Body Cavity ◽  
Seldinger Technique ◽  
Recovery Times ◽  
Hospital Stays ◽  
Magnetic Resonance Imaging Mri ◽  
Lower Morbidity

Vascular and Interventional Radiology, more succinctly known as Interventional Radiology (IR), is the subspecialty of Medical Imaging or Radiology that deals with diagnosis and treatment using minimally invasive procedures under imaging guidance. Initially, fluoroscopy was the only imaging modality available, but ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) are also currently being used for guidance. One of the basic skills used by interventional radiologists is the Seldinger technique: the introduction of a needle into a body cavity or lumen allowing passage of a wire guide, which in turn facilitates the insertion of a tube or catheter. Many IR procedures have supplanted more invasive surgical techniques, with the resultant benefits of lower morbidity and mortality, shorter hospital stays and recovery times, and lower costs. Traditionally, obstetricians and interventional radiologists seldom interacted with one another, but their collaboration in patient care and research is increasing as obstetricians realise the value of IR, and as the myriad techniques and tools in the interventionalist's armamentarium expand and evolve.

Electron Microscopy of Metal-Matrix Composites

1970 ◽  
Vol 28 ◽  
pp. 404-405
Author(s):  
A. Lawley ◽  
M. R. Pinnel ◽  
A. Pattnaik
Keyword(s):  
Electron Microscopy ◽  
Metal Matrix Composites ◽  
Metal Matrix ◽  
Critical Evaluation ◽  
Elastic Behavior ◽  
Matrix Composites ◽  
Directionally Solidified ◽  
Fracture Characteristics ◽  
Broad Program

As part of a broad program on composite materials, the role of the interface on the micromechanics of deformation of metal-matrix composites is being studied. The approach is to correlate elastic behavior, micro and macroyielding, flow, and fracture behavior with associated structural detail (dislocation substructure, fracture characteristics) and stress-state. This provides an understanding of the mode of deformation from an atomistic viewpoint; a critical evaluation can then be made of existing models of composite behavior based on continuum mechanics. This paper covers the electron microscopy (transmission, fractography, scanning microscopy) of two distinct forms of composite material: conventional fiber-reinforced (aluminum-stainless steel) and directionally solidified eutectic alloys (aluminum-copper). In the former, the interface is in the form of a compound and/or solid solution whereas in directionally solidified alloys, the interface consists of a precise crystallographic boundary between the two constituents of the eutectic.

The Expanding Role of Echocardiography in Interventional Cardiology

2010 ◽  
Vol 6 (2) ◽  
pp. 71 ◽  
Author(s):  
Lindsay A Smith ◽  
Amit Bhan ◽  
Mark J Monaghan ◽  
◽  
◽  
...  
Keyword(s):  
Interventional Procedures ◽  
Imaging Modality ◽  
Interventional Cardiology ◽  
Design And Technology ◽  
Team Approach ◽  
Medical Problems ◽  
Multidisciplinary Team Approach ◽  
Case Selection ◽  
Optimal Imaging

Echocardiography provides excellent realtime imaging of the heart, making it the imaging modality of choice immediately before, during and after cardiac interventional procedures. It helps to guide case selection and execution of the intervention, evaluates the effects of the intervention and enables early detection of complications. Advances in the design and technology of medical devices and delivery systems, coupled with demand for alternative non-surgical therapies for common medical problems, have led to an increase in the volume, variety and complexity of non-coronary cardiac interventional procedures performed. Many of these procedures require a multidisciplinary team approach and demand optimal imaging to ensure successful outcomes. The aim of this article is to review the expanding role of echocardiography in non-coronary interventional cardiology in adults.

Philosophical and Pedagogical Views of Yu. F. Samarin

2019 ◽  
Vol 54 ◽  
pp. 209-218
Author(s):  
Lev E. Shaposhnikov
Keyword(s):  
National Identity ◽  
Social Development ◽  
Educational Policy ◽  
Critical Evaluation ◽  
Educational Process ◽  
Educational Context ◽  
The Government ◽  
Role Of Religion

The paper analyses the evolution of Yu. Samarin’s ideas from rationalism to “holistic knowledge”. Special attention is paid to the philosopher’s conceptualization of the key role of religion for a nation. The author also examines the scholar’s position concerning the promotion of patriotism as an important impetus for social development. Emphasis is made on analyzing the interaction of universal and national aspects in the educational process, as well as on the value of national identity in the field of humanities. The article also presents Yu. Samarin’s critical evaluation of the government educational policy and his suggestions on increasing its effectiveness. The author notes the relevance of Yu. Samarin’s views for the contemporary philosophical and educational context.

Role of Cardiac MRI in Detecting Familial Hypertrophic Cardiomyopathy: Review

2016 ◽  
Vol 1 (1) ◽  
pp. 4
Author(s):  
Marymol Koshy ◽  
Bushra Johari ◽  
Mohd Farhan Hamdan ◽  
Mohammad Hanafiah
Keyword(s):  
Hypertrophic Cardiomyopathy ◽  
Magnetic Resonance ◽  
Genetic Disorder ◽  
Familial Hypertrophic Cardiomyopathy ◽  
Non Invasive ◽  
Wide Range ◽  
Proper Diagnosis ◽  
Magnetic Resonance Imaging Mri ◽  
Potential Use

Hypertrophic cardiomyopathy (HCM) is a global disease affecting people of various ethnic origins and both genders. HCM is a genetic disorder with a wide range of symptoms, including the catastrophic presentation of sudden cardiac death. Proper diagnosis and treatment of this disorder can relieve symptoms and prolong life. Non-invasive imaging is essential in diagnosing HCM. We present a review to deliberate the potential use of cardiac magnetic resonance (CMR) imaging in HCM assessment and also identify the risk factors entailed with risk stratification of HCM based on Magnetic Resonance Imaging (MRI).

The Role of Atrial Fibrosis Detected by Delayed - Enhancement MRI in Atrial Fibrillation Ablation

2020 ◽  
Vol 16 (2) ◽  
pp. 135-144 ◽  
Author(s):  
Zsuzsanna Kis ◽  
Astrid Amanda Hendriks ◽  
Taulant Muka ◽  
Wichor M. Bramer ◽  
Istvan Kovacs ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Imaging Modality ◽  
Final Analysis ◽  
Atrial Fibrosis ◽  
Atrial Wall ◽  
Af Ablation ◽  
Left Atrial Wall ◽  
Cmr Imaging

Introduction: Atrial Fibrillation (AF) is associated with remodeling of the atrial tissue, which leads to fibrosis that can contribute to the initiation and maintenance of AF. Delayed- Enhanced Cardiac Magnetic Resonance (DE-CMR) imaging for atrial wall fibrosis detection was used in several studies to guide AF ablation. The aim of present study was to systematically review the literature on the role of atrial fibrosis detected by DE-CMR imaging on AF ablation outcome. Methods: Eight bibliographic electronic databases were searched to identify all published relevant studies until 21st of March, 2016. Search of the scientific literature was performed for studies describing DE-CMR imaging on atrial fibrosis in AF patients underwent Pulmonary Vein Isolation (PVI). Results: Of the 763 citations reviewed for eligibility, 5 articles (enrolling a total of 1040 patients) were included into the final analysis. The overall recurrence of AF ranged from 24.4 - 40.9% with median follow-up of 324 to 540 days after PVI. With less than 5-10% fibrosis in the atrial wall there was a maximum of 10% recurrence of AF after ablation. With more than 35% fibrosis in the atrial wall there was 86% recurrence of AF after ablation. Conclusion: Our analysis suggests that more extensive left atrial wall fibrosis prior ablation predicts the higher arrhythmia recurrence rate after PVI. The DE-CMR imaging modality seems to be a useful method for identifying the ideal candidate for catheter ablation. Our findings encourage wider usage of DE-CMR in distinct AF patients in a pre-ablation setting.

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