Monitoring Detrusor Oxygenation and Hemodynamics Noninvasively during Dysfunctional Voiding

Figure 4

A composite graph of urine flow and volume with NIRS parameters in a 72-year-old man with obstructive lower urinary tract symptoms. He had a trabeculated bladder on cystoscopic exam and increased bladder wall thickness on ultrasound. Following permission to void (P) total hemoglobin (tHb) falls; there is a drop in oxygenated hemoglobin (O₂Hb) associated with a rise beginning in deoxygenated hemoglobin (HHb). Following uroflow start (S), this rising (positive) trend in HHb continues while O₂Hb and tHb continue to fall until urine flow is decreasing. This implies an imbalance in oxygen supply and demand, which begins on initiation of voiding and continues beyond Qmax.