Residual urine, underactive detrusor function, and the nature of detrusor/sphincter dyssynergia

Transurethral incision of the bladder neck to treat bladder neck dysfunction and voiding dysfunction in patients with high-level spinal cord injuries

PURPOSE

Detrusor-sphincter dyssynergia (DSD) and bladder neck dysfunction (BND) may cause voiding dysfunction in patients with spinal cord injury (SCI). We report the surgical outcomes in patients with high-level SCI who underwent transurethral incision of the bladder neck (TUI-BN).

PATIENTS AND METHODS

Twenty-two patients with SCI at or above the mid-thoracic level who presented with voiding dysfunction due to BND with different types of DSD received TUI-BN. Surgical outcome was determined by comparing preoperative with postoperative urodynamic parameters and clinical presentations. Satisfactory outcome was defined as having improvement of AUA/IPSS quality-of-life (QoL) index by >or=2.

RESULTS

Among the patients, 19 (86.4%) were men and 3 (13.6%) were women. Thirteen patients had cervical and nine had thoracic SCI. Postoperatively, spontaneous voiding by abdominal triggering with an open urethral sphincter was noted in 19 patients (86%) and AD had resolved in 15 patients (88.2%). Detrusor pressure decreased significantly in 9 patients who had a high voiding pressure at baseline, and increased significantly in 13 patients who showed impaired detrusor contractility preoperatively. Eighteen patients (82%) reported satisfactory outcome, increased maximum flow rate (Q(max)), decrease in postvoid residual (PVR) postoperatively. In addition, 82% of the patients were catheter free or reported a decrease in the frequency of clean intermittent catheterization after TUI-BN.

CONCLUSIONS

TUI-BN is effective in restoring spontaneous voiding, increasing Q(max), and decreasing PVR in high-level SCI patients. TUI-BN also leads to improvement in reducing bladder outlet resistance, reduction in occurrence of AD episodes, and improvement in QoL.

Bladder neck dysynergia in spinal cord injury

Urodynamic evaluations were performed in 43 male patients with spinal cord injuries, before any therapeutic decisions, and a minimum of 5 mo following the injury. Results were subdivided according to level of injury. Mean detrusor contraction pressures, incidence of detrusor-sphincter dysynergia (DSD), and incidence of detrusor-bladder neck dysynergia (DBND) were calculated. The incidence pattern of DBND was found to follow closely the incidence pattern of DSD, with the highest incidence among the upper thoracic injuries, considerably more than among the cervical injuries. A significantly higher resting detrusor pressure differential was found among the patients with DBND. This was felt to represent sympathetic dysfunction and poor accommodation and is proposed to be secondary to adrenergic detrusor neoinnervation.

Detrusor contractility in hyperreflexic bladders (from intracerebral neuropathies) versus unstable and stable unobstructed ones

Three male patient groups of 20 subjects each have been assessed urodynamically by pressure flow study, namely, patients with detrusor hyperreflexia (DH) due to intracerebral neuropathies were compared with subjects bearing a condition of idiopathic detrusor instability, as well as with a control group of males showing normal urodynamic findings. Detrusor contractility proved greater in the unstable patients, but did not differ significantly between those with DH and the controls. Such results may suggest that intracerebral neuropathies leading to DH have no influence on, whilst the factors responsible for detrusor instability are strongly related to, the degree of activation of bladder muscle mechanical capability.

Characterisation of detrusor contractile function in relation to old age

This report describes an age-related clinical study of detrusor muscle function using urodynamic data obtained from 1391 women and 324 men of different age groups who were free from overt neurological disease and diabetes. Isometric detrusor function during unstable activity was assessed by integrating the calculated force of unstable detrusor activity during filling of the bladder. Isotonic voiding activity was measured by calculating the velocity constant Q*, which reflects the speed of detrusor muscle shortening. In addition, the change in detrusor pressure on initiation of voiding and the post-micturition residual urine volume were recorded. Older patients of both sexes had higher residual urine volumes. Older women showed lower detrusor shortening velocities. There were no age-related differences in isometric detrusor function. Older women showed a tendency for the detrusor contraction to fail on initiation of voiding, whereas older men did not demonstrate this difference. Voiding dysfunction in late life was more marked amongst women and seemed to be related to a failure of isotonic detrusor function with no related changes in isometric function.

Neurological defects of the voiding reflex arcs in chronic urinary retention and their relation to spina bifida occulta

A group of 37 patients (24 female and 13 male) with chronic urinary retention and without demonstrable mechanical obstruction had neurophysiological measurements of their lower urinary tracts to detect any neurological abnormality which might relate to the disorder. These consisted of measurements of the electrosensitivity of the dorsal nerve of the penis/clitoris and of the urethra, measurement of the sacral reflex latencies (SRL) from dorsal nerve to urethra and to anus and between urethra and anus and EMG studies of the urethral and anal sphincters. The results suggest that female patients in particular have significant neurogenic defects in the voiding reflex arcs which find their clinical expression in detrusor underactivity with urinary retention. Plain X-rays of the renal tracts (KUB films) were also studied for the presence of spina bifida occulta. The prevalence of this defect was significantly higher than in normal controls, suggesting that in some of these patients the nerve defect might be related to a tethered cord in association with spina bifida occulta.

Ultrasound as an alternative to intravenous urography in prostatism

Seventy-five patients, with uncomplicated benign prostatic hypertrophy referred for pre-prostatectomy assessment, were studied to determine whether renal tract ultrasound combined with plain films of kidney, ureters and bladder could provide an acceptable alternative to intravenous urography (IVU). All patients had both IVU and ultrasound. Bladder residual urine volumes were calculated by ultrasound measurements. Fifty-nine (78%) patients had normal IVU and ultrasound. Twelve (16%) had both abnormal IVU and abnormal ultrasound. Four (6%) had positive findings on one examination not detected on the other: two of these occurred with ultrasound and two with IVU. Measurement of residual volume of urine in the bladder by ultrasound and IVU is discussed. The combination of ultrasound and a plain radiograph of the urinary tract provides more information and should replace IVU in the preoperative assessment of patients with uncomplicated benign hypertrophy of the prostate.

The pressure-volume plot and prediction of treatment outcome in female incontinence

A graphic representation of the micturition cycle by a pressure-volume plot has been obtained in 120 women, both incontinent patients and normal controls. The pattern of contraction during voiding allowed prediction of the outcome of treatment. Patients with urethral sphincter incompetence and a sustained detrusor contraction had a good result from colposuspension even if detrusor instability was found during filling. Where the urethral sphincter was competent, patients with urge incontinence with or without detrusor instability during filling cystometry had a good response to drugs, providing a sustained detrusor contraction was present during voiding. Urethral sphincter incompetence was characterised by a low detrusor voiding pressure.