Other causes of voiding difficulty include medications (such as antihistamines and anticholinergic agents), infections (in particular, herpes simplex virus, and urinary tract infections), obstruction (following bladder neck surgery, or in women with advanced pelvic organ prolapse), overdistension, severe constipation (particularly in the elderly), and, rarely, psychogenic factors. Fowler’s syndrome refers to unexplained urinary retention occurring as an isolated phenomenon (144). Such women usually are between 20 and 35 years of age. Commonly the first retention episode will be triggered by an event such as surgery or childbirth. Retention rarely resolves but is not associated with the development of other disorders.
Evaluation Evaluation of a woman with voiding difficulty begins with a careful physical examination. Advanced pelvic organ prolapse may contribute to urinary retention, but it is unlikely that prolapse above the level of the vaginal introitus will be the sole cause of retention. When in doubt, the woman can wear a pessary for a week to see whether elevating the prolapse reduces the voiding difficulty. Occasionally pelvic masses—in particular, low anterior myomas—may cause urinary retention. Abnormal findings detected during neurologic examination of the perineum and lower extremities may suggest the need to focus on the spine. Urodynamic evaluation will help determine whether the woman has an obstruction (manifested by high detrusor pressures during voiding or by no urethral relaxation during voiding) or whether the detrusor muscle is not contracting. The latter is not necessarily indicative of a neurogenic disorder in women, because a large minority of normal healthy women void by urethral and pelvic ﬂoor muscle relaxation alone, with no detrusor contraction. Cystourethroscopy may reveal an obstructing lesion, such as a polyp, tumor, ureterocele, or ball-valve stone. Usually, the evaluation reveals no obvious source, and treatment can commence.
Treatment The mainstay in the treatment of voiding difficulty is clean, intermittent self-catheterization (145). The most important protection against urinary tract infection is frequent and complete bladder emptying rather than avoiding the introduction of a foreign body into the bladder. Selfcatheterization allows the patient to accomplish this task using a small (14-Fr) plastic catheter that she inserts through the urethra into the bladder, draining its contents. The catheter is then removed, washed with soap and water, dried, and stored in a clean, dry place. Elaborate sterile procedures are not necessary. Bacteria are introduced into the bladder in this process, and the urine of women after self-catheterization regimens will always be colonized with bacteria; however, this condition should not be treated unless symptomatic infection occurs.
In addition to decreasing urinary urgency and incontinence caused by detrusor overactivity, neuromodulation of the sacral nerve roots may help women with nonobstructive urinary retention (122). In a trial of 177 patients with idiopathic urinary retention, those who had greater than 50% improvement in baseline voiding symptoms during a test stimulation period qualified for surgical implantation of InterStim. Of these, 37 were randomly assigned to early implantation, whereas 31 in the control group delayed implantation for 6 months. Improved voiding occurred in 83% of the implant group compared with 9% of the control group at 6 months (146). It appears that the long-term success rates of InterStim for urinary retention remain high. In a trial following patients for 5-years after implantation, 71% of the patients with urinary retention had successful outcomes (147). Although this technology requires a surgical procedure, many women favor this therapy over lifelong self-catheterization.