Outcome after treatment of detrusor-sphincter dyssynergia by temporary stent

OBJECTIVES: To evaluate follow-up treatments used after treatment of detrusor-sphincter dyssynergia (DSD) by a temporary urethral sphincter stent. MATERIALS AND METHODS: Between February 1994 and June 2003, 147 men with a mean age of 41.3+/-14.4 years were treated by temporary urethral stent inserted across the external sphincter for DSD. The underlying neurologic disease was quadriplegia in 85 cases, multiple sclerosis in 24 cases and paraplegia in 21 cases. A Nissenkorn (Bard) stent was used in 130 cases and a Diabolo (Porgès) stent was used in 17 cases. All patients were either unable to or they refused to perform intermittent self-catheterization. DSD was demonstrated by urodynamic studies in every case. RESULTS: The mean duration of temporary stenting was 10.15+/-16.07 months. After temporary stenting, 92 patients were treated by permanent stent (Ultraflex, Boston Scientifics), 7 started intermittent self-catheterization, 12 had repeated changes of the temporary stent, 4 had an indwelling catheter, 3 underwent cystectomy with non-continent diversion, 2 were treated by endoscopic sphincterotomy, 1 was treated by bladder neck incision, 1 was treated by neuromodulation and 1 was treated by cystostomy. Fifteen patients were lost to follow-up. Two patients died during follow-up (not related to DSD). CONCLUSION: After treatment of DSD by a temporary urethral sphincter stent, 70.7% of patients subsequently require a permanent urethral sphincter stent. This period allows selection of patients unlikely to benefit from permanent urethral sphincter stent.     

SPHINCTERIC STENT VERSUS EXTERNAL SPHINCTEROTOMY IN SPINAL CORD INJURED MEN: PROSPECTIVE RANDOMIZED MULTICENTER TRIAL

PURPOSE: In a prospective randomized multicenter trial we compared the treatment results of conventional external sphincterotomy with those of UroLume sphincteric stent prosthesis placement in men with spinal cord injury and external detrusor-sphincter dyssynergia. MATERIALS AND METHODS: We randomized 57 men with spinal cord injury in whom urodynamics verified external detrusor-sphincter dyssynergia into 2 groups to undergo either sphincter defeating procedure. We compared the primary urodynamic parameter of maximum detrusor pressure, and secondary urodynamic parameters of bladder capacity and post-void residual urine volume in men who underwent sphincterotomy or sphincteric stent placement. Parameters were measured preoperatively, and 3, 6, 12 and 24 months postoperatively. Patients completed questionnaires regarding voiding sensation and quality of life issues at each followup visit. RESULTS: Demographic data of the 26 patients treated with sphincterotomy and the 31 treated with sphincteric stent placement were statistically similar. Preoperatively mean maximum detrusor pressure plus or minus standard deviation in sphincterotomy and stent cases was 98.3 +/- 27.6 and 95.7 +/- 27.7 cm. water, respectively (p = 0.73). At 12 months mean maximum detrusor pressure decreased to 48.9 +/- 16.4 and 52.6 +/- 31.6 cm. water in the sphincterotomy and stent groups, respectively (p = 0). Preoperatively mean bladder capacity in sphincterotomy and stent cases was 245 +/- 158 and 251 +/- 145 ml., respectively (p = 0.87). Bladder capacity did not change significantly in either treatment group throughout followup. Preoperatively mean post-void residual urine volume in the sphincterotomy and stent groups was 212 +/- 163 and 168 +/- 114 ml., respectively (p = 0.33). Residual urine volume decreased in each group at some but not all followup evaluations. The duration of hospitalization was greater for sphincterotomy than stenting (p = 0.036). Six stents required explantation. CONCLUSIONS: The UroLume stent is as effective as conventional external sphincterotomy for treating external detrusor-sphincter dyssynergia. However, sphincteric stent placement is advantageous because it involves shorter hospitalization and is potentially reversible.     

Reversible Clinical Outcome After Sphincter Stent Removal

Purpose

We determined whether the self-expanding sphincter stent, a potential alternative to conventional external sphincterotomy for the treatment of detrusor external sphincter dyssynergia, causes a permanent effect on the lower urinary tract.

Materials and Methods

Four spinal cord injured men with voiding symptoms of detrusor external sphincter dyssynergia as noted by complete urological evaluation, including a video urodynamic study, were treated with the self-expanding sphincter stent. However, the device was explanted 6 months or longer after insertion in all 4 cases due to stent migration (3) and difficulty with condom catheter urinary drainage (1).

Results

All stents were removed completely without damage to the urethra. Mean voiding pressure decreased from 62.5 plus/minus 39.4 to 20.7 plus/minus 6.5 cm. water after sphincter stent placement. One year after stent explanation mean voiding pressure remained unchanged from preoperative values of 58.5 plus/minus 21.5 cm. water. No patient had stress urinary incontinence or endoscopically apparent urethral strictures.

Conclusions

The stent can be removed even after complete epithelialization and an extended interval without damage to external sphincter function or urethral stricture formation. The urinary sphincter stent is an effective, reversible treatment for patients with detrusor external sphincter dyssynergia.     

Management of detrusor-external sphincter dyssynergia

Detrusor-external sphincter dyssynergia (DSD) is a debilitating problem in patients with spinal cord injury. DSD carries a high risk of complications, and even life expectancy can be affected. The mainstay of treatment is the use of antimuscarinic medication and catheterization, but in those for whom this is not possible external sphincterotomy has been the traditional management route. External sphincterotomy, however, is associated with significant risks, including hemorrhage, erectile dysfunction and the need for repeat procedures, and over the last decade alternatives have been investigated, such as urethral stents and botulinum toxin injection. We present a review of DSD, including the current management strategies and prospects for future treatment.     

Memokath stents for the treatment of detrusor sphincter dyssynergia (DSD) in men with spinal cord injury: the Princess Royal Spinal Injuries Unit 10-year experience

STUDY DESIGN: Medical records review. OBJECTIVE: To assess the effectiveness of the Memokath (Engineers and Doctors A/S, Denmark) thermosensitive stent as a 'nondestructive' means of reducing bladder outlet resistance by treating detrusor sphincter dyssynergia (DSD) of neurogenic bladder dysfunction associated with spinal cord injury. SETTING: Spinal Injuries Unit, Sheffield, England. METHODS: A medical records review was performed to examine our experience of Memokaths over the last 10 years. During this time, 29 patients with spinal cord injury (17 tetraplegic and 12 paraplegic) underwent stenting of the external urethral sphincter either for prevention of dysreflexic symptoms, high residual urine volumes and subsequent urinary tract infection (UTI) or for protection of the upper tracts. RESULTS: A total of 33 stents were inserted into 29 men (25-77 years) with suprasacral spinal cord injury. Initial results showed that the Memokath was effective in almost all for relief of dysreflexic symptoms and elimination of DSD on pressure flow urodynamics. However, to date, 30 of the 33 stents have been removed. The overall mean working life of the Memokath was 21 months. Four stents were removed electively and 23 for complications, which included stent migration (seven) and blockage (14). Single-ended stents were more prone to migration, which was rare after 1 year (1-13 months, median 3 months, mean 5.5 months). Stent blockage by encrustation or prostatic ingrowth did not occur before 12 months (12-45 months, median 30, mean 27.9 months). CONCLUSIONS: In selected patients, temporary, thermo-expandable (Memokath) stents are effective in the treatment of DSD. The 'working life' of a Memokath stent is 21 months; however, complications do occur which may necessitate removal. Our overall experience with Memokath stents was disappointing. In future, Memokath stents will only be inserted after careful consideration in patients with prior 'failed' transurethral sphincterotomy or with caution in patients suitable for reconstructive surgery.     

A urethral stent for the treatment of detrusor-striated sphincter dyssynergia

OBJECTIVE: To assess the technique, efficacy and complications of the Ultraflex urethral stent (Boston Scientific Corp., Boston, MA) for the treatment of detrusor-striated sphincter dyssynergia (DSD). PATIENTS AND METHODS: Forty consecutive patients with DSD who had a Ultraflex stent placed in the membranous urethra were evaluated prospectively. DSD was caused by spinal cord injury in 30, multiple sclerosis in six and other neurological diseases in four. All patients were either tetraplegic or paraplegic and unable to use intermittent self-catheterization. Previous bladder management consisted of an indwelling catheter in 15 patients, chronic suprapubic catheters in two, intermittent catheterization in nine, and trigger reflex micturition in 14. The Ultraflex stent was placed under local anaesthesia. The stents were 50 mm long in 36 patients, 45 mm in two and 40 mm in two. The mean (SD) follow-up was 16.9 (13. 8) months. RESULTS: The mean (SD) residual urine decreased from 245. 9 (117) mL before stenting to 65.2 (19.3) mL at 12 months afterward (n = 19). One stent was removed at 13 months for chronic prostatic and urinary tract infection leading to autonomic dysreflexia. There was no stent stenosis and 17 of 18 stents had > 75% epithelial coverage at one year. None of the stents migrated. Seven patients underwent secondary bladder neck incision through the stent. The stent length was increased in four patients using a second overlapping distal stent, twice during the first procedure and twice within 6 months because the sphincter was inadequately covered. CONCLUSIONS: The Ultraflex stent achieved the expected results for a prosthetic sphincterotomy and appears to be an appropriate but less invasive treatment for DSD.     

Experimental and clinical studies of urethral anesthesia on etiology and treatment of detrusor-sphincter dyssynergia

We studied whether detrusor-sphincter synergia during micturition was obtained by means of urethral anesthesia with lidocaine hydrochloride in five thoracic spinal cats and eight clinical cases with detrusor-sphincter dyssynergia. In thoracic spinal cats with detrusor-sphincter dyssynergia, urethral anesthesia produced detrusor-sphincter synergia, an increase in the maximum bladder pressure and a decrease in the residual volume. In clinical cases with detrusor-sphincter dyssynergia, urethral anesthesia produced detrusor-sphincter synergia or a decrease in the external urethral sphincter activities during micturition, and a decrease in the maximum urethral closure pressure and the residual volume. There were no remarkable changes of the external urethral sphincter activities during urine storage phase before and after urethral anesthesia in both spinal cats and clinical cases. These results suggest that urethral anesthesia blocks the urethro-urethral contraction reflex and secondarily activates vesico-urethral relaxation reflex. The block of urethral sensory nerves is thought to effectively treat detrusor-sphincter dyssynergia.     

Botulinum toxin as a new therapy option for voiding disorders: current state of the art

Botulinum toxin is a presynaptic neuromuscular blocking agent inducing selective and reversible muscle weakness up to several months when injected intramuscularly in minute quantities. Different medical disciplines have discovered the toxin to treat mainly muscular hypercontraction. In urology, indications for botulinum-A toxin have been neurogenic detrusor overactivity, detrusor-sphincter dyssynergia, motor and sensory urge and, more recently, chronic prostatic pain. The available literature was reviewed using Medline Services. The keywords "botulinum-A toxin", "detrusor-sphincter dyssynergia", "neurogenic bladder", "spinal cord injury", "denervation", "chronic prostatic pain", "chronic urinary retention" were used to obtain references. A toxin injection is effective to treat detrusor-sphincter dyssynergia when injected either transurethrally or transperineally. After treatment, external urethral sphincter pressure, voiding pressure and post-void residual volume decreased. The effect lasts between 2 to 9 months depending on the number of injections. Best indications seem to be multiple sclerosis and incomplete spinal cord injury patients suffering from neurogenic detrusor overactivity and detrusor-sphincter dyssynergia. According to the previous results, the use of botulinum-A toxin injections into the external urethral sphincter has been extended to a variety of bladder obstructions and to decrease outlet resistance in patients with acontractile detrusor. In cases of successful treatment, spontaneous voiding re-occurs and catheterization can be resumed. Injections of the toxin into the external urethral sphincter also seem to have a beneficial effect on chronic prostatic pain, presumably by reducing hypertonicity and hyperactivity of the external urethral sphincter. Injections of botulinum-A toxin into the detrusor muscle has first been tested to treat neurogenic detrusor activity in spinal cord injured patients and in myelomeningocele children. Long lasting (mean 9 months) detrusor relaxation occurs after injection of usually 300 units of Botox). Continence is restored in about 95% of the patients and anticholinergic drugs can be markedly reduced or even stopped. Excellent results of botulinum-A toxin injections into the detrusor in neurogenic detrusor overactivity have lead to an expansion of this treatment to incontinence due to idiopathic detrusor overactivity. Although preliminary results are promising, adequate dosage of the toxin required for this indication is not yet known. In conclusion, it appears that botulinum toxin injection into either the external urethral sphincter or the detrusor offers new promising treatment options for many different urological dysfunctions. However, large controlled trials are absolutely required to establish the role of botulinum-A toxin injections in the fields of urology and neurourology on evidence based medicine.     

Oral nitric oxide donors: a new pharmacological approach to detrusor-sphincter dyssynergia in spinal cord injured patients?

PURPOSE: Detrusor-sphincter dyssynergia is a common cause of bladder outlet obstruction in spinal cord injured patients and leads to poor bladder emptying and high bladder pressures, which if left untreated might cause renal failure. In this study, we tested the recently published hypothesis that oral administration of a nitric oxide donor could be a new pharmacological approach to treat detrusor-sphincter dyssynergia in humans with spinal cord injury. METHODS: 12 male spinal cord injured patients presenting with neurogenic detrusor overactivity and detrusor-sphincter dyssynergia were studied. 6 performed clean intermittent catheterisation and 6 used suprapubic tapping for bladder emptying. During cystometry the bladder was filled until the first overactive bladder contraction accompanied by detrusor-sphincter dyssynergia occurred while bladder and external urethral sphincter pressures were continuously recorded. Then the bladder was emptied and the patients received 10 mg of isosorbide dinitrate sublingually. Resting pressures were recorded and cystometry was repeated starting 15 min after drug administration. Maximal and mean values for bladder and external urethral sphincter pressures were calculated in both fillings and statistically compared by analysis of variance for repeated measurements (level of significance p < 0.05). RESULTS: Nitric oxide significantly reduced external urethral sphincter pressures at rest (p < 0.05) and during dyssynergic contraction (p < 0.05) while bladder pressures at rest and during contraction as well as the reflex volume remained unchanged. In the patients who used suprapubic tapping for bladder emptying the mean post triggering residual volume was significantly reduced (p < 0.05). CONCLUSIONS: Oral administration of nitric oxide donors significantly reduced bladder outlet obstruction due to detrusor-sphincter dyssynergia suggesting a role for nitric oxide in inhibitory neurotransmission to the urethral sphincter. This new approach could offer a potential pharmacological option to treat detrusor-sphincter dyssynergia in spinal cord injured patients.     

The mesh wallstent in the treatment of detrusor external sphincter dyssynergia in men with spinal cord injury: a 12-year follow-up

OBJECTIVE: To assess the long-term effectiveness of the UroLume trade mark wallstent (Pfizer Inc., UK) in the treatment of detrusor external sphincter dyssynergia (DESD) in quadriplegic patients. PATIENTS AND METHODS: Twelve patients with quadriplegia secondary to spinal trauma underwent external striated sphincter stenting with the UroLume wallstent instead of an external sphincterotomy for DESD (mean age 41.8 years, range 26-65). The level of injury was C4 in two, C5 in four, C6 in four, C7 in one and T6 in one. All patients were shown by preoperative video-cystometrography (VCMG) to have DESD and high-pressure, hyper-reflexic bladders with incomplete emptying. RESULTS: Seven of the 12 patients had a mean (range) follow-up of 12.7 (12.17-13.6) years; two others were lost to follow-up at 1 and 3 years and both remained free of complications during that time. Two patients developed encrustation causing obstruction, requiring stent removal within a year of insertion. Another patient with an adequately functioning stent died 7 years after surgery (chest infection). Urodynamic follow-up of the seven patients showed a significantly sustained reduction in maximum detrusor pressure and duration of detrusor contraction at> 10 years of follow-up. Five of the seven patients developed bladder neck dyssynergia of varying degrees, as shown on VCMG; all were successfully treated with bladder neck incision. There were no problems with stent migration, urethral erosion, erectile dysfunction or autonomic dysreflexia. CONCLUSION: Permanent urethral stenting using the UroLume wallstent is effective in managing DESD and provides an acceptable long-term alternative to sphincterotomy. Subsequent bladder neck dyssynergia is the main complication but this can be managed successfully with bladder neck incision. Importantly, unlike sphincterotomy, there is no significant interference with erectile function. Also, the procedure is reversible, minimally invasive and requires a shorter hospital stay.     

Radical transurethral resection of the prostate in male paraplegics revisited: further clinical experience and urodynamic considerations for its effectiveness

We report our experience with radical transurethral resection of the prostate performed on 89 male spinal cord injury subjects. The over-all success rate of modified sphincterotomy was 90 per cent, although there was a 14 per cent recurrence rate with time. Urodynamically, success was characterized by a statistically significant reduction in the degree of detrusor-sphincter dyssynergia, an increase in vesical compliance and a reduction in detrusor hyperreflexia. These results suggest an effect on the distal sphincteric area by the adrenergic system in the genesis of detrusor-sphincter dyssynergia. It is suggested that radical transurethral resection of the prostate exerts this effect via a surgical sympathectomy, while continence is preserved by the activity of the untouched external urethral sphincter.     

Urethral stent for the treatment of detrusor-sphincter dyssynergia: evaluation of the clinical, urodynamic, endoscopic and radiological efficacy after more than 1 year

PURPOSE: We studied the intermediate-term clinical, urodynamic, endoscopic and radiological efficacy of the Ultraflex urethral stent (Boston Scientific Co., Boston, Massachusetts) for the treatment of detrusor-sphincter dyssynergia (DSD) in spinal cord injured patients. MATERIALS AND METHODS: A total of 47 consecutive men presenting with DSD due to spinal cord injury (39) or various spinal cord diseases (9) were treated with the Ultraflex stent. DSD was demonstrated by urodynamic assessment with electromyographic recording of the striated urethral sphincter muscle activity. RESULTS: Postoperatively, all patients voided by reflex. The number of patients with symptomatic postoperative urinary tract infection decreased significantly (p <0.001). Urodynamic assessment (mean followup +/- SD 2.2 +/- 1.3 years) showed reduction of mean peak detrusor pressure from 65.7 +/- 27.8 to 46.4 +/- 28.8 cm H2O (p <0.005) and reduction of mean residual urine from 231.6 +/- 168.1 to 70.3 +/- 85.6 ml (p <0.0005). Mean urethral closing pressure was markedly reduced from 73.9 +/- 40.9 to 23.8 +/- 25.1 cm H2O (p <0.0005). Mean endoscopic followup was 1.7 +/- 1.1 years. Mean percentage of epithelialization was 90.8% +/- 19.7%, and no obstructive granulation tissue or stone encrustation was observed inside the stent. On ultrasound signs of hydronephrosis persisted in only 1 of 8 patients. There were no immediate postoperative complications. Complementary bladder neck incision was performed in 21% of patients. CONCLUSIONS: The Ultraflex stent appears to be effective for intermediate-term treatment of DSD on the basis of clinical, urodynamic, endoscopic and radiological parameters.     

UroLume stents: lessons learned

PURPOSE: The UroLume (American Medical Systems, Minnetonka, Minnesota) endoprosthesis has been commercially available since 1990 and has been advocated for use in men with urethral stricture disease and detrusor-sphincter dyssynergia due to spinal cord injury. Despite reports of its success and ease of removal, we have noted management problems in several complex cases. MATERIALS AND METHODS: We retrospectively analyzed the outcome of 10 men who required several additional procedures or experienced complications following UroLume placement. RESULTS: Of the patients 4 had detrusor-sphincter dyssynergia and 6 had urethral stricture disease. All patients with detrusor-sphincter dyssynergia required hospitalization for management of urosepsis within 4 to 10 months of stent placement, and all 4 experienced stent migration requiring placement of a tandem stent (3), bladder neck resection (3) or sphincterotomy (1). Two men were in retention following placement of a second stent and required stent explantation. Of the other 6 men 2 had bulbar and 3 had membranous urethral disease, and 1 had a severe bladder neck contracture following radical retropubic prostatectomy. Strictures recurred within the stent lumen in all 6 men and/or adjacent to it in 3. At least 1 repeat procedure was required in all 6 men (within 6 months in 5), and 1 experienced significant bleeding during open explantation which required perineal urethrostomy. CONCLUSIONS: In our referral experience stent migration and recurrent stenosis were noted following UroLume insertion. Placement of a tandem stent was associated with urethral obstruction. In many cases these adverse outcomes may be secondary to improper patient selection. Therefore, judicious use of the UroLume stent and proper case selection are essential since stent removal is not always straightforward.     

Neuropeptide Y- and vasoactive intestinal polypeptide-containing nerves in the intrinsic external urethral sphincter in the areflexic bladder compared to detrusor-sphincter dyssynergia in patients with spinal cord injury

Specimens of urethra were obtained from patients with cervical and thoracic spinal cord lesion with detrusor-sphincter dyssynergia and from patients with lower motor neurone lesion with detrusor areflexia, undergoing transurethral sphincterotomy. Neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) in nerves associated with both the smooth and striated muscle components of the urethral sphincter were studied immunohistochemically and by immunoassay. In patients with detrusor-sphincter dyssynergia following cervical and thoracic spinal cord injury, NPY- and VIP-immunoreactive varicose nerve fibres were seen in both the smooth and striated muscle components of the urethral sphincter. In the smooth muscle, NPY- and VIP-immunoreactive nerves did not appear to have any particular orientation, but in the striated muscle region they were found to run along the length of individual muscle fibres. In patients with detrusor areflexia following lower motor neurone lesion, while the pattern, density and fluorescence intensity of NPY- and VIP-immunoreactive nerves in the smooth muscle of the sphincter mechanism appeared the same as seen in patients with detrusor-sphincter dyssynergia, there was a marked increase in the density of these nerves in the striated muscle region of the sphincter mechanism. Quantitation of the peptides by immunoassay was consistent with the histochemical findings, with significantly higher levels of both NPY and VIP in the striated muscle of patients with lower motor neurone lesion, compared to those with cervical and thoracic spinal cord lesion, p = 0.04. NPY and VIP levels in urethral smooth muscle were in the same range in lower motor neurone lesion patients and cervical and thoracic spinal cord lesion patients. We conclude that there are increased NPY- and VIP-containing fibres in striated muscle of the intrinsic external urethral sphincter in patients with areflexic bladder compared with those with detrusor-sphincter dyssynergia.     

Long-term followup of the North American multicenter UroLume trial for the treatment of external detrusor-sphincter dyssynergia

PURPOSE: We determine the long-term efficacy and safety of the UroLume stent as minimally invasive treatment for external detrusor-sphincter dyssynergia in spinal cord injured men. MATERIALS AND METHODS: A total of 160 spinal cord injured men with a mean age plus or minus standard deviation of 36.3 +/- 12.1 years (range 16 to 74) were prospectively treated with an endoprosthesis at 15 centers as part of the North American UroLume trial for external detrusor-sphincter dyssynergia. Urodynamic parameters, including voiding pressure, residual urine volume and bladder capacity, were compared before treatment and at 1, 2, 3, 4 and 5 years after treatment. RESULTS: Mean voiding pressure was 75.1 +/- 28.2 cm. water before treatment in the 160 patients, and 37.4 +/- 23.9 at year 1 in 97, 39.5 +/- 22.2 at year 2 in 84, 42.6 +/- 27.3 at year 3 in 61, 46.3 +/- 33.2 at year 4 in 57 and 44.2 +/- 28.9 cm. at year 5 in 41 after stent insertion (p <0.001). Residual urine volume decreased after stent placement and was maintained throughout the 5-year followup (p <0.001). Mean cystometric capacity remained constant from 269 +/- 155 before insertion to 337 +/- 182 ml. 5 years later (p = 0.17). Hydronephrosis and autonomic dysreflexia improved or stabilized in most patients with functioning stents. Stent explant was necessary in 24 patients (15%), of whom 4 (16.7%) had another stent implanted. CONCLUSIONS: The UroLume stent demonstrates long-term safety and efficacy for the treatment of external detrusor-sphincter dyssynergia. The outcome was similar in men with and without previous sphincterotomy.     

The effect of modified transurethral sphincterotomy on autonomic dysreflexia

Autonomic dysreflexia continues to be a major problem in spinal cord injury patients. In our report 16 patients with spinal cord lesions above the T6 level and a history of autonomic dysreflexia also had detrusor-sphincter dyssynergia. Of these patients 12 (75 per cent) had evidence of dysreflexia during cystometry. In addition, the dysreflexic response in blood pressure was shown to correlate with the high intravesical and urethral pressures measured during cystometry. Modified transurethral sphincterotomies subsequently were performed on all patients as recommended therapy for detrusor-sphincter dyssynergia. Repeat cystometry revealed significant decreases in intravesical and urethral pressures compared to before sphincterotomy (p less than 0.001) along with an associated significant decrease in blood pressure (p less than 0.01). Other dysreflexic responses also were markedly attenuated. These results suggest an association among detrusor-sphincter dyssynergia, high intravesical and urethral pressures, and autonomic dysreflexia. Our data indicate further that the frequency and magnitude of autonomic dysreflexia can be diminished significantly by modified external sphincterotomy.     

Experience with urethral stent explantation

PURPOSE: We examined the timing, causes and results of the explantation of UroLume (American Medical Systems, Minnetonka, Minnesota) urethral stents. MATERIALS AND METHODS: The North American Study Group enrolled 465 patients in a trial of UroLume stent placement, including 69 (14.8% of the series) who required removal of a total of 73 stents (15.6% of stents) in 7 years. The time of explantation, reason for stent removal and local histological findings were determined from patient charts and reviewed in relation to the indication for stent placement. RESULTS: In patients treated for bladder outlet obstruction secondary to benign prostatic hyperplasia 23% of the stents were removed, as were 5% of those implanted in patients with bulbar urethral stricture and 22% of those in patients with detrusor-sphincter dyssynergia (see figure). Of the explantations 43.8% were done during year 1. Migration and/or inappropriate placement was the cause in 38.4% of cases. The most common stent site tissue finding was focal inflammation with a hyperplastic tissue response. Stent specific malignant changes were not observed. Stent removal was feasible with no sequelae. CONCLUSIONS When used appropriately, the UroLume endoprosthesis has a low incidence of failure. Stent removal is technically feasible and options are available for subsequent therapy. Local tissue reaction is minimal.     

Video urodynamic findings in men with the central cord syndrome

PURPOSE: The central cord syndrome reportedly has a favorable prognosis and rehabilitation outcome. However, to our knowledge the status of the lower urinary tract in patients with the central cord syndrome is unclear. We report on 22 men with the central cord syndrome who were evaluated by video urodynamics. MATERIALS AND METHODS: From 1986 to the present we identified 22 men with a mean age of 51 years who had the central cord syndrome and were included in the Houston Veterans Affairs spinal cord registry. All patients underwent video urodynamic evaluation a mean of 34.5 months after injury. RESULTS: Video urodynamic testing for vesicourethral dysfunction was normal in 3 patients, while it showed bladder outlet obstruction secondary to benign prostatic hyperplasia in 2, detrusor areflexia in 4, external detrusor-sphincter dyssynergia in 11, detrusor hyperreflexia with a synergistic external urethral sphincter in 1 and detrusor hypocontractility in 1. Urinary tract infection recurred in 3 patients with external detrusor-sphincter dyssynergia and urolithiasis developed in 2. CONCLUSIONS: Urodynamic testing revealed a high incidence of external detrusor-sphincter dyssynergia in men with the central cord syndrome. Due to the potential for upper tract deterioration all patients with the central cord syndrome should undergo baseline urodynamic studies. Those at high risk for upper tract deterioration with external detrusor-sphincter dyssynergia or a loss of compliance should be treated more aggressively with clean intermittent catheterization and anticholinergic medication when possible.     

Diagnostic discordance of electromyography (EMG) versus voiding cystourethrogram (VCUG) for detrusor-external sphincter dyssynergy (DESD)

AIMS: Detrusor sphincter dyssynergia (DSD) is defined as: "a detrusor contraction concurrent with an involuntary contraction of the urethral and/or periurethral striated muscle." In neurogenic etiology, this usually refers to involuntary contraction of the external striated sphincter and has classically been termed detrusor-external sphincter dyssynergia (DESD). There is currently no consensus regarding diagnosis [specifics of electromyographic (EMG) or voiding cystourethrographic (VCUG) determination], and little data on how well these modalities correlate. We explore the diagnostic congruence for DESD between needle EMG and VCUG in the neurogenic population. METHODS: Consecutive studies performed by a single urodynamicist at a major neurologic center were reviewed. Presence of DESD was determined by increased wire needle EMG activity and/or by dilated bladder neck and proximal urethra during detrusor contraction, in the absence of valsalva or attempt to inhibit voiding. Minimal acceptable criterion for agreement between the two tests was set at 70%. RESULTS: Fourty nine patients were diagnosed with DESD, had a videourodynamic study available, and had no history of sphincterotomy or stent. Binomial testing demonstrated significant disagreement (P < 0.000) in observed proportions. There was 60% agreement (28 patients) and 40% disagreement (21 patients) between EMG and VCUG for diagnosis of DESD. CONCLUSIONS: We found significant disagreement between needle EMG and VCUG for a positive diagnosis of DESD. A combination of EMG and VCUG may identify more cases of DESD than either modality alone and underscores the need for more strict criteria when defining this entity from a urodynamic standpoint.