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Updated: Feb 27, 2026

Ultrasonography of the Adult Male Urinary Tract for Urinary Functional Testing
Published on: August 14, 2019
Urodynamics of men with urinary retention
David P Guo1, Craig V Comiter1, Christopher S Elliott1,2
1Department of Urology, Stanford University School of Medicine, Stanford, California, USA.
Objectives:
To describe the urodynamic characteristics of men with urinary retention, and to show the diverse treatment plans based on urodynamic findings.
Methods:
We carried out a 3-year retrospective review of men with urinary retention who were referred to our clinic for urodynamic evaluation. Men with a history of neurogenic voiding dysfunction or major pelvic surgery were excluded. Multichannel videourodynamic studies were carried out, and the subsequent treatment modality offered was recorded.
Results:
A total of 67 men with urinary retention and a median age of 68 years underwent urodynamic evaluation. The median maximum flow rate was 3 mL/s, and the median detrusor pressure at maximum flow was 54 cm H2 O. Bladder outlet obstruction was diagnosed in 60%. Detrusor underactivity was present in 73% according to the bladder contractility index; however, just 29% were classified as having detrusor underactivity according to isometric detrusor pressure, an alternative measure of contractility. A total of 76% of patients had low detrusor reserve (<20 cm H2 O). Based on urodynamic findings, just 57% of patients were offered de-obstructive surgery.
Conclusions:
In the present cohort, just 60% of men with urinary retention showed urodynamic evidence of bladder outlet obstruction. Depending on how contractility is measured (bladder contractility index vs isometric detrusor pressure), the rate of detrusor underactivity varies. The majority of men with retention had a low detrusor reserve. Given the wide spectrum of urodynamic findings in men with retention, surgical intervention might not be necessary for all. Furthermore, a careful consideration of urodynamics can assist in the selection of optimal treatment.
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