Use in contrast enhancement

The differences between low molecular weight Gd-based CAs and macromolecular CAs stem mainly from their pharmacodynamic and pharmacokinetic properties, that is, what the CA does to the body, and vice versa. In addition to the observed relaxivity, the dynamic relaxivity is another parameter that is used in contrast-enhanced MRA in the presence of different types of CAs. The dynamic relaxivity describes the relaxivity results from both bound and non-bound complexes. For example, a comparison of the strongly HSA-bound MS-325 with the non-HSA-bound P792 in rabbit showed P792 to have a more constant dynamic relaxivity [114], A constant pharmacokinetics profile is also favorable for MRA analysis. 

Iontophoresis by definition is the process of transport of ions into or through a tissue by the use of an applied potential difference across the tissue [52], Depending on the physicochemical characteristics of a molecular species, electrorepulsion is usually the primary mechanism of transdermal transport for ions, whereas electroosmosis and increased passive diffusion (as a result of the reduced barrier properties) are more prominent for neutral species [53]. In contrast, enhancement in flux for neutral or weakly charged species during electroporation arises predominantly from the reduced barrier properties of the membrane, whereas direct electrorepulsion is usually of secondary importance [25],... 

Chart 2.3. Various dyes used as contrast-enhancement materials. The poly-silanes are useful in the mid-UV region (308-313 nm), the other materials are designed for use in the near-UV region (365- 36 nm). 

In some clinical situations, the intrinsic contrast of the tissue is not sufficient to distinguish pathological from healthy tissue. Therefore, the use of contrast-enhancing agents has become an integral part of... 

Roberts, H.C., et al.. Quantitative measurement of micro-vascular permeability in human brain tumors achieved using dynamic contrast-enhanced MR imaging correlation with histologic grade. AJNR Am J Neuroradiol, 2000. 21(5) p. 891-9. 

It is our goal to perfect our technique in order to get more consistent results, reduce complications, and establish uterine fibroid embolization for a durable time period. Large calibrated microspheres are equally effective to smaller non-calibrated particles to target the peri-fibroid arterial plexus. Calibrated microspheres are so easy to deliver through microcatheters that one may predict the progressive replacement of non-spherical particles in the near future. MRI has become the reference imaging tool before and after embolization. The use of contrast-enhanced studies allows early detection... 

Carr JC, Nemcek AA Jr, Abecassis M et al (2003) Preoperative evaluation of the entire hepatic vasculature in living liver donors with use of contrast-enhanced MR angiography and true fast imaging with steady-state precession. J Vase Interv Radiol 14 441-449... 

An aq. soln. at 31° contains 30% a-pyr, 64% P-pyr, 2.5% a-fur, 3.5% P-fur and 0.02% aldehyde. Active ingredient of Levovist , used in echo-enhancement in sonographic Doppler-B-mode imaging. Ultrasound contrast medium. 

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