Figure 1: An example of voiding session without potential motion artifacts. Pressure flow study with simultaneous near-infrared spectroscopy (NIRS) of a man with LUTS bladder outlet obstruction. Thirty seconds of baseline was averaged between points “X” and “A” for all NIRS parameters. The amplitudes of change in deoxy-hemoglobin (HHb), oxy-hemoglobin (O2Hb), and total hemoglobin ( ) were calculated as follows: amplitude of each NIRS parameter = its value at point “B”—the average value of 30 s baseline of that parameter. There is an overall rise in the Hbsum curve led mainly by the relevant rise in the HHb curve which may imply an overall increase in the rate of oxygen consumption during voiding in this subject. : intravesical pressure, : abdominal pressure, : detrusor pressure, : urinary flow rate.