Benign Prostatic Hyperplasia: Evaluation of T1, T2, and Microvascular Characteristics With T1-Weighted Dynamic Contrast-Enhanced MRI

Purpose: To evaluate microvascular and relaxation parameters of prostate and nearby muscle in patients with benign prostatic hyperplasia (BPH). and to examine measurement reproducibility. Materials and Methods: In this prospective study, 13 patients with BPH were imaged twice prior to surgery. The imaging protocol included a three-dimensional (31)) Inversion-recovery turbo field-echo measurement of T-1, a multiecho measurement of T-2, and a high temporal resolution (1.5 seconds per volume) dynamic contrast-enhanced (DCE) acquisition. The DCE data were analyzed using a distributed parameter tracer kinetics model to provide estimates of perfusion (F-b), extraction fraction (E), mean transit time (T-c), and extravascular-extracellular volume (V-e) in both the central gland (CG) and the peripheral zone (PZ) of the prostate, and in nearby muscle. Precision of these estimates was calculated using a bootstrap technique and the reproducibility was evaluated using the within-patient coefficient of variation (wCV). Results: The microvascular parameters were estimated in the prostate with high precision; in particular, E, F-b, and v(e) had median CVs of <= 6%, <= 4%, and <= 5%, respectively. Reproducibilities of the T, and T2 measurements were excellent (wCV <= 4%), and reproducibility of the other parameters reflected values seen in previous studies. Conclusion: Microvascular and relaxation properties of BPH can be measured precisely with reproducibilities for a distributed parameter tracer kinetics model that are comparable to those for a simpler model. Measurements of T, and T2 were highly reproducible.