| Autor: |
Raffi, Kalayciyan, Friedrich, Wetterling, Sabine, Neudecker, Stefan, Haneder, Norbert, Gretz, Lothar R, Schad |
| Rok vydání: |
2012 |
| Předmět: |
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| Zdroj: |
Journal of magnetic resonance imaging : JMRI. 38(3) |
| ISSN: |
1522-2586 |
| Popis: |
To develop a sodium-MRI ((23) Na-MRI) method for bilateral renal sodium concentration (RSC) measurements in rat kidneys at 9.4 Tesla (T).To simultaneously achieve high B1 -field homogeneity and high receive sensitivity a dual resonator system composed of a double-tuned linearly polarized (1) H/(23) Na volume resonator and a newly developed two-element (23) Na receive array was used. In conjunction with three-dimensional (3D) ultra-short Time-to-Echo sequence a quantification accuracy of ± 10% was achieved for a nominal spatial resolution of (1 × 1 × 4) mm(3) in 10 min acquisition time. The technique was applied to study the RSC in six kidneys before and after furosemide-induced diuresis.The loop diuretic agent induced an increase of cortical RSC by 22% from 86 ± 16 mM to 105 ± 18 mM (P = 0.02), whereas the RSC in the inner medulla decreased by 38% from 213 ± 24 mM to 132 ± 25 mM (P = 0.8×10(-4) ). The RSC changes measured in this study agreed well with the qualitative sodium signal intensity variations reported elsewhere.Furosemide-induced diuresis has been investigated accurately with herein presented quantitative (23) Na-MRI technique. In the future, RSC quantification could allow for defining pathological and nonpathological RSC ranges to assess sodium concentration changes, e.g., induced by drugs. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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