Cystometry and pressure-flow study (pre-TUR and post-TUR). a) Preoperative-UDS: Three involuntary detrusor contractions occurred at 42, 138, and 160 mL during filling. She voided with a Qmax of 4 mL/sec and a Pdet of 177 cmH2O. These values suggested female BOO. b) Postoperative UDS: Only one involuntary detrusor contraction occurred at 286 mL, just before voiding. Her maximum desire-to-void volume increased to 306 mL. She voided with a Qmax of 15 cm/s and a Pdet of 62 cmH2O. A postoperative PFS demonstrated a considerable improvement in voiding. Q: flow, Pves: vesical pressure, Pabd: abdominal pressure, Pdet: detrusor pressure, red arrows: voluntary bladder contraction.