Abstract
Recent clinical studies using color Doppler ultrasonography (CDUS) have revealed the influence of bladder ischemia caused by bladder outlet obstruction (BOO) on lower urinary tract function and lower urinary tract symptoms (LUTS). In 2003, Belenky et al. reported the increased vascular resistance of the internal iliac artery represented as the resistive index (RI) in patients with severe BOO. In 2007 and 2008, there were consecutive reports about bladder ischemia in patients with benign prostatic hyperplasia (BPH). Bladder RI was improved overall after medical therapy with alpha-blockers and surgical treatment of BPH (transurethral resection of the prostate: TURP). However, persistent detrusor overactivity after surgery was associated with persistently high bladder RI with subsequent reduced perfusion. We also studied bladder ischemia using CDUS in patients with BPH. Our studies showed that 1) bladder RI correlated with BOO grade and prostatic volume; 2) bladder RI was improved after relieving BOO by TURP or 5-alpha reductase inhibitor, but bladder RI after medical or surgical therapy was less improved in patients with persistent overactive bladder (OAB); and 3) less improvement of bladder RI after medical or surgical therapy was associated with remaining BOO or higher incidence of hypertension (an arterial sclerosis risk factor). Simple and more accurate measurement of bladder blood flow using ultrasonography would reveal the long-term impact of bladder ischemia on LUTS and the reversibility of lower urinary tract dysfunction and bladder ischemia after medical or surgical treatment.
