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Updated: Jul 11, 2026

Ultrasonography of the Adult Male Urinary Tract for Urinary Functional Testing
Published on: August 14, 2019
Videourodynamic analysis of pathophysiology of men with both storage and voiding lower urinary tract symptoms
1Department of Urology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan. hck@tzuchi.com.tw
Objectives:
Lower urinary tract symptoms (LUTS) are highly prevalent among men; however, not all men with LUTS have urodynamically confirmed bladder outlet obstruction. Overactive bladder symptoms are often caused by bladder dysfunctions alone or in combination with bladder outlet obstruction. A detailed diagnosis to identify the causes of LUTS in men seems mandatory to correctly target different therapy to the various underlying pathologic features.
Methods:
A total of 1407 male patients referred for investigation of LUTS were included in this study. All patients had both storage and voiding symptoms. A videourodynamic study was performed for the diagnosis of bladder dysfunction and bladder outlet dysfunction. The videourodynamic results were also correlated with patient age and compared with the presenting symptoms.
Results:
The videourodynamic study revealed that of the 1407 patients with bladder dysfunction, 148 (10.5%) had increased bladder sensation, 724 (51.5%) had detrusor overactivity, 149 (10.6%) had detrusor underactivity, and 82 (5.8%) had a combination of detrusor overactivity and detrusor underactivity. The causes of bladder outlet dysfunction included bladder neck dysfunction in 19 patients (1.4%), benign prostatic obstruction in 413 (29.4%), urethral sphincter pseudodyssynergia in 30 (2.1%), and poor relaxation of urethral sphincter in 283 (20.1%).
Conclusions:
The results of this study have indicated that LUTS can result from a complex interplay of pathophysiologic features that can include bladder dysfunction and bladder outlet dysfunction such as benign prostatic obstruction or poor relaxation of the urethral sphincter. About one third of men with LUTS who were older than 55 years of age had benign prostatic obstruction. Patients younger than 55 years old were more likely to have poor relaxation of the urethral sphincter as a likely cause of LUTS.
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Urinary Bladder
In males, the bladder is situated in front of the rectum, while in females, it is positioned anterior to the vagina and uterus. The bladder floor contains an inverted triangular area called the trigone, defined by the two ureteric...

