The lower urinary tract includes the bladder and urethra, which allows for storage and timely expulsion of urine. Voiding dysfunction is a broad term, used to describe the condition where there is poor coordination between the bladder muscle and the urethra. This results in incomplete relaxation or over-activity of the pelvic floor muscles during voiding. Voiding symptoms represent a continuum of what is referred to as Lower Urinary Tract Symptoms (LUTS).
LUTS can occur during bladder filling (storage), emptying (voiding), post urination or a combination. Storage symptoms are often irritative and can include urgency, frequent urination, frequent nighttime urination or involuntary loss of urine. In men, voiding symptoms can be related to obstructive causes, and thus symptoms such as urinary hesitancy, difficulty in emptying bladder or straining, weak stream or urinary dribbling can occur.
In men, there are many potential etiologies of voiding dysfunction. Common causes of obstructive symptoms include an enlarged prostate due to benign prostatic hyperplasia (BPH) or prostatitis. Less common causes are urethral stricture (scar tissue), bladder stones or bladder tumors (benign or cancer). Pelvic floor hyperactivity are also found in men. Irritative symptoms can results from similar etiologies, but also from other causes including bladder infection, bladder stone or tumor. Symptoms can occur if there is neuro-sensory dysregulation within the bladder, which can be reflected as sensory instability, inappropriate bladder contractions, bladder hyperreflexia or poor bladder compliance. Neuro-sensory dysregulation may be the result of bladder structural or physiologic changes due to chronic, untreated BPH.