Aims To evaluate bladder vascular resistance before and after transurethral resection of the prostate (TURP). Methods Thirty-three patients with lower urinary tract symptoms (LUTS) suggestive of benign prostatic obstruction were prospectively studied. We analyzed correlations of bladder vascular resistance with various factors including age, vascular risk factors, symptom score, prostate volume (PV), and urodynamic parameters before and 3 months after TURP. Using contrast-enhanced color Doppler ultrasonography for measuring bladder vascular resistance, resistive index (RI) of vesical arteries was calculated. Results Compared with healthy young male (n?=?10) and age-matched controls (n?=?10), the study patients had a higher preoperative RI (0.403 +/- 0.100, 0.436 +/- 0.042, and 0.561 +/- 0.089, respectively; P?<?0.01). Preoperative RI was significantly higher in patients with PV?=?60?ml versus <60?ml (0.604 +/- 0.078 vs. 0.525 +/- 0.082; P?<?0.01), and in patients with severe obstruction versus mild/moderate obstruction (0.615 +/- 0.087 vs. 0.534 +/- 0.078; P?=?0.017). Overall RI decreased significantly after TURP (from 0.561 +/- 0.089 to 0.450 +/- 0.086; P?<?0.001). In patients with persistent urgency after TURP, RI was less improved than in those without urgency after TURP (change of RI 0.068 +/- 0.098 vs. 0.135 +/- 0.090; P?<?0.05). This study was limited by a small sample size. Conclusions Bladder vascular resistance in patients with LUTS was elevated in correlation with PV and severity of obstruction. Although bladder vascular resistance decreased significantly after TURP in overall patients, less reduction of vascular resistance was related to persistent urgency after TURP, implying that persistent urgency after TURP might be caused by persistent bladder ischemia. Neurourol. Urodynam. 31:659663, 2012. (C) 2012 Wiley Periodicals, Inc.