Near-Infrared Spectroscopy of the Urinary Bladder during Voiding in Men with Lower Urinary Tract Symptoms: A Preliminary Study

Table 1

Comparison of demographic, urodynamic, and near-infrared spectroscopy (NIRS) parameters between the obstructed and unobstructed groups.

Statistics (median)	Obstructed 𝑛=28	Unobstructed 𝑛=8	P value*
Age (yr)	68 (52–86)	68.5 (42–76)	0.99
BMI (Kg/m^2)	26.5 (20–32)	26.6 (24–34)	0.69
IPSS	19 (7–28)	12 (5–33)	0.23
Prostate volume	42 (23–160)	32 (21–50)	0.15
Voided volumes	172 (16–600)	201 (97–424)	0.69
𝑄max (mL/s)	5 (2–12)	7 (2–9)
𝑃det⋅𝑄max (cmH2O)	69 (37–175)	39 (26–47)
PVR (mL)	169 (0–682)	103 (0–350)	0.69
HHb (µmol/L)	1.8 (−4.0–6.2)	−4.5 (−5.6–2.1)	0.045*
O2Hb (µmol/L)	1.1 (−5.8–7.5)	0.32 (−1.5–4.8)	0.09
Hbsum (µmol/L)	2.6 (−9.0–9.5)	0.33 (−4.8–2.6)	0.23

BMI: body mass index, IPSS: International Prostate Symptom Score, PSA: prostate specific antigen, 𝑄_max: maximum flow rate, PVR: postvoid residual urine, HHb: deoxy-hemoglobin, O₂Hb: oxy-hemoglobin, Hb_sum: total hemoglobin (Hb_sum = HHb + O₂Hb), 𝑃_{det⋅𝑄max}: detrusor pressure at maximum flow rate.
^∗𝑃 value <0.05 is significant (Mann Whitney 𝑈 test).