Effect of Gd-DTPA-BMA on blood and myocardial T1 at 1.5T and 3T in humans

✍ Scribed by Puneet Sharma; Josh Socolow; Salil Patel; Roderic I. Pettigrew; John N. Oshinski

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 552 KB
• Volume: 23
• Category: Article
• ISSN: 1053-1807
• DOI: 10.1002/jmri.20504

✦ Synopsis

Abstract

Purpose

To compare T~1~ values of blood and myocardium at 1.5T and 3T before and after administration of Gd‐DTPA‐BMA in normal volunteers, and to evaluate the distribution of contrast media between myocardium and blood during steady state.

Materials and Methods

Ten normal subjects were imaged with either 0.1 mmol/kg (N = 5) or 0.2 mmol/kg (N = 5) of Gd‐DTPA‐BMA contrast agent at 1.5T and 3T. T~1~ measurements of blood and myocardium were performed prior to contrast injection and every five minutes for 35 minutes following contrast injection at both field strengths. Measurements of biodistribution were calculated from the ratio of ΔR~1~ (Δ__R__~1myo~/Δ__R__~1blood~).

Results

Precontrast blood T~1~ values (mean ± SD, N = 10) did not significantly differ between 1.5T and 3T (1.58 ± .13 sec, and 1.66 ± .06 sec, respectively; P > 0.05), but myocardium T~1~ values were significantly different (1.07 ± .03 sec and 1.22 ± .07 sec, respectively; P < 0.05). The field‐dependent difference in myocardium T~1~ postinjection (T~1~@3T – [email protected]) decreased by approximately 72% relative to precontrast T~1~ values, while the field‐dependent difference of blood T~1~ decreased only 30% postcontrast. Measurements of Δ__R__~1myo~/Δ__R__~1blood~ were constant for 35 minutes postcontrast, but changed between 1.5T and 3T (0.46 ± .06 vs. 0.54 ± .06, P < 0.10).

Conclusion

T~1~ is significantly longer for myocardium (but not blood) at 3T compared to 1.5T. The differences in T~1~ due to field strength are reduced following contrast administration, which may be attributed to changes in Δ__R__~1myo~/Δ__R__~1blood~ with field strength. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.