Hemodynamic analysis of bladder tumors using T1-dynamic contrast-enhanced fast spin-echo MRI

To evaluate the hemodynamics of bladder tumors, we developed a method to calculate change in R(1) value (ΔR(1)) from T(1)-dynamic contrast-enhanced fast spin-echo magnetic resonance imaging (T(1)DCE-FSE-MRI).

On a 1.5-T MR system, T(1)DCE-FSE-MRI was performed. This study was applied to 12 patients with urinary bladder tumor, i.e. urothelial carcinoma. We compared ΔR(1)-time and ΔSI-time between a peak in the ΔR(1)-time and ΔSI-time curve occurred during the first pass within 60s. Next, we assessed the slope of increase for 180s after CA injection (Slope(0-180)).

The mean slope of the first pass was significantly higher for bladder tumors on both the ΔR(1)-time and the ΔSI-time curve compared with normal bladder walls. Moreover, a significant difference was apparent between bladder tumors and normal bladder walls on the mean Slope(0-180) in the ΔR(1)-time curve. However, no significant difference in the mean Slope(0-180) was observed on the ΔSI-time curve between bladder tumors and normal bladder walls.

T(1)DCE-FSE-MRI offers three advantages: quantitative analysis; high-quality (i.e., artifact-free) images; and high temporal resolution even for SE images. Use of ΔR(1) analysis with T(1)DCE-FSE-MRI allows more detailed information on the hemodynamics of bladder tumors to be obtained and assists in differentiation between bladder tumors and the normal bladder wall.