Ni-DTPA doped agarose gel--a phantom material for Gd-DTPA enhancement measurements
| Autor: | B. Shuter, Ps Tofts, James M. Pope |
|---|---|
| Rok vydání: | 1993 |
| Předmět: |
Gadolinium DTPA
Time Factors Gadolinium Biomedical Engineering Biophysics Analytical chemistry chemistry.chemical_element Contrast Media Imaging phantom chemistry.chemical_compound Nuclear magnetic resonance Nickel Organometallic Compounds Humans Radiology Nuclear Medicine and imaging Chelation Drug Interactions Aqueous solution Sepharose Relaxation (NMR) Doping Temperature Pentetic Acid Magnetic Resonance Imaging Models Structural Solutions chemistry Drug Design Agarose Gels |
| Zdroj: | Magnetic resonance imaging. 11(1) |
| ISSN: | 0730-725X |
| Popis: | In order to study the relationship between the concentration of Gd-DTPA in tissue, and the resulting changes in relaxation times and signal intensity, a phantom material that has similar relaxation times to tissue and that can be doped with Gd-DTPA is required. The "tissue-equivalent" material should not contain Gd; nor should it alter the relaxivities of Gd-DTPA from their values in aqueous solution (R1 = 4.5 sec-1 mM-1; R2 = 5.5 sec-1 mM-1 at 1.5 T). Conventional materials, based on CuSO4-, MnCl2-, or GdCl3/LaCl3-agarose mixtures, are not suitable, since Gd is displaced from the Gd-DTPA chelate. The new material, consisting of Ni-DTPA dissolved in agarose, is easy to prepare and does not interact with Gd-DTPA. Its relaxation times are stable; relaxivity R1 was within 4% of its aqueous value over 109 days. T1s have low dependence on temperature (0.2-1.0%/degrees C at 21 degrees C) and on field strength, allowing the material to be used as a relaxation time standard for quality assurance. Equations giving the concentration of Ni-DTPA and agarose to produce a required T1 and T2 are provided. |
| Databáze: | OpenAIRE |
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