The use of the Memokath stent in the treatment of detrusor sphincter dyssynergia in spinal cord injury patients: a single-centre seven-year experience

AIMS: A retrospective analysis of our seven-year experience with the Memokath urethral stent for the treatment of detrusor sphincter dyssynergia (DSD) in spinal cord injured (SCI) patients. PATIENTS AND METHODS: Twenty five patients with SCI underwent rhabdosphincter Memokath stent insertion. The mean age was 45.5 years (range 32-65 years). The level of injury was cervical in 14 and thoracic in 11 patients. All patients were shown to have neurogenic detrusor overactivity with DSD associated with high detrusor pressures and incomplete emptying on pre-operative video-cystometrograms (VCMG). The Memokath stent was inserted using a standardized protocol. Follow-up assessment included blood chemistry, ultrasound scan (upper tracts and residual urine) at one and three months after insertion, and a follow-up VCMG at six months. The pre-operative and six-month post-operative VCMG results were analysed by the paired t-test and p value <0.05 was taken as significant. RESULTS: There was a significant reduction in maximum detrusor pressure, duration of contraction and residual urine volume (p<0.05) on the VCMG six months after insertion of the stent. At present six patients have a Memokath stent in situ at a mean of 34.7 months (range 6-86 months). Nineteen stents were removed for several reasons at a mean of 20.3 months (range 0.25-41 months). These include, exacerbation of autonomic dysreflexic symptoms (n=3); stent migration (n=7); encrustation and stone formation (n=5); incomplete bladder emptying without obstruction (n=3); entrance into fertility program (n=1). CONCLUSION: The Memokath stent is safe, easy and quick to insert with minimal trauma to the urethra. It is effective in the management of DSD and decreasing the detrusor pressure and residual urine volume in SCI patients. Moreover the ease of its removal in a non-traumatic fashion makes this stent an attractive option when patients are still contemplating the method of bladder management, in those wishing to be involved in fertility program and in recently SCI patients who may recover some manual dexterity to perform clean intermittent self-catheterisation. It must be remembered that this is a temporary stent, as our study clearly shows that the majority are removed within two years of insertion.     

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.     

Long-term result of Memokath urethral sphincter stent in spinal cord injury patients

Background

Memokath urethral sphincter stents are used to facilitate bladder emptying in patients with spinal cord injury, but long term follow-up has not been reported.

Methods

Case series of ten men with spinal cord injury who underwent insertion of Memokath stents and were followed for up to nine years.

Results

Within four years, the stent had to be removed in nine out of ten patients because of: extensive mucosal proliferation causing obstruction to the lumen of the stent; stone around the proximal end of the stent, incomplete bladder emptying, and recurrent urinary infections; migration of the stent into the bladder related to digital evacuation of bowels; large residual urine; concretions within the stent causing obstruction to flow of urine, and partial blockage of the stent causing frequent episodes of autonomic dysreflexia. In one patient the stent continued to function satisfactorily after nine years.

Conclusions

The Memokath stent has a role as a temporary measure for treatment of detrusor-sphincter dyssynergia in selected SCI patients who do not get recurrent urinary infection and do not require manual evacuation of bowels.

     

Outcome of dual flange metallic urethral stents in the treatment of neuropathic bladder dysfunction after spinal cord injury

Abstract Purpose: To review the results of metallic urethral stents used in patients with neuropathic bladder dysfunction after spinal cord injury (SCI). Patients and Methods: In a rehabilitation unit for SCI and stroke in Cape Town, South Africa, we performed a case note review of dual flange Memokath stents placed from March 2008 until October 2011. Stents were placed rather than performing an external sphincterotomy in selected patients. With the patient under deep general anesthesia, a thermosensitive expandable metallic stent was positioned over the internal and external urethral sphincters. Results: In total, 33 stents were placed in 28 male patients. SCI was cervical in 23 patients and thoracic in 5. Average follow-up was 18 months (range 1-40 months, median 18 months). The most common indications were repeated catheter blockage in eight patients and urinary tract infection in six. The average time from SCI to stent insertion was 79 months (range 1-468 months, median 21 months). Severe autonomic dysreflexia was present in 17 cases before stent placement and in 7 after stents were placed (P=0.003). Stents failed in 15 patients (45%) and were removed. The most common reason for failure was stone formation. Comparing the group of patients with stents lasting >20 months (n=11) to the group with stent removal before 20 months (n=10), the mean time between SCI and stent placement was 31 vs 119 months (P=0.057). Medium term results (up to 27 months) were significantly influenced by earlier stent placement (P=0.0484). One major complication was stent migration that caused an urethrocutaneous fistula.     

Thermo-expandable Intra-prostatic Stent in the Treatment of Acute Urinary Retention in Elderly Patients with Significant Co-morbidities

We assess the use of thermo-expandable intra-prostatic stent (Memokath, Engineers and Doctors A/S, Denmark) for the treatment of acute urinary retention (AUR) in men with significant co-morbidities for transurethral resection of prostate (TURP). We evaluate the pre- and post-operative complications, duration of stents in-situ and patients quality of life after the stent insertion. Patients with significant co-morbidities presenting with AUR were selected, who were unfit for TURP. The co-morbidities included ischaemic heart disease, congestive heart failure, and chronic obstructive pulmonary disease. The exclusion criteria were bladder tumour and atonic bladder. The Memokath stents were inserted using a flexible cystoscope under local anaesthesia. The patients were followed up at 3 and 6 months after the procedure and the ones who remained alive were asked to complete self-administered questionnaires and IPSS scores. Fifteen men with acute urinary retention were recruited for stent insertion with the mean age of 87 years. No peri-operative complications were recorded. Three patients died after the insertion with functional Memokath in-situ. Nine patients had good functioning stents post-operatively, and remain catheter free up to 30 months after the procedure. The mean duration of stent life was 18 months. Three long-term complications were detected, including stent migration and prostate overgrowth. The Memokath is a good option for frail elderly patients presenting with AUR. The procedure is safe and has minimal long term complications. The stent also provides a sustained good quality of life for patients and avoids the necessity of long term catheterisation.     

Feasibility of a temporary urethral stent through the striated sphincter in patients in the early phase (6 months) of spinal cord injury

OBJECTIVE: To assess the feasibility of a temporary urethral stent through the striated sphincter in patients in the early phase (before 6 months) of spinal cord injury (SCI) in a department of neurological rehabilitation. METHODS: Fourteen consecutive men with SCI with urinary retention within 6 months after SCI were prospectively treated. Thirteen patients were tetraplegic (C2 to C7) and 1 was paraplegic. All patients were managed with indwelling catheters (10) or intermittent catheterization (4). The Nissenkorn polyurethane urethral stent was inserted across the external sphincter under local anesthesia for an anticipated 4-month duration. RESULTS: No perioperative complications were encountered. Hospital mean stay at the urological department was 1.9 days (range 1-4 days). All patients had good emptying of the bladder (residual urine less than 100 ml) and were free of all types of catheterization. Five stents had to be repositioned in the first 2 weeks, 1 was removed for obstruction at 2.5 months. There was no lithiasis, no upper urinary tract alteration, no symptomatic infection nor local discomfort during follow-up. At a mean of 3.7 months after implantation, 10/14 (71.5%) patients chose sphincterotomy by permanent urethral stent and 4 had stent removal for learning of self-intermittent catheterization (3) and indwelling catheter (1). CONCLUSIONS: The temporary sphincter stent is a new, feasible and reversible technique to manage neuropathic bladder dysfunction in the early phase after SCI. A randomized study on intermittent catheterization should be conducted. It should consider patients' and nursing caregivers' evaluations.     

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.     

Sphincterotomy and the treatment of detrusor-sphincter dyssynergia: current status,future prospects

STUDY DESIGN: Literature review of current treatment options for detrusor-sphincter dyssynergia (DSD) in spinal cord injury. OBJECTIVES: To review the outcomes and complications associated with external sphincterotomy and to summarise the results and complications of alternative treatment options for detrusor-sphincter dyssynergia in spinal cord injury. In addition, we propose a potential alternative future drug treatment for external sphincter dyssynergia based upon recent research on the neuropharmacology of the external urethral sphincter. SETTING: The National Spinal Injuries Centre, Stoke Mandeville Hospital, Aylesbury, UK. METHODS: Medline search from 1966 to 2002 using the words 'external sphincterotomy', 'detrusor-sphincter dyssynergia' and 'neurogenic bladder combined with surgery'. RESULTS: While external sphincterotomy is an effective treatment for DSD, a significant number of men following this procedure continue to have high intrarenal pressures, recurrent urinary infection or troublesome autonomic dysreflexia and a worryingly high proportion demonstrate persistently raised leak point pressures, putting them at subsequent risk of renal damage. Alternative treatments for external sphincter dyssynergia include urethral stents and balloon dilatation, both of which are effective. However, over the long term stents can undergo encrustation and there remains a definite risk of stent migration necessitating stent removal or replacement. Balloon dilatation of the external sphincter is associated with a risk of subsequent stricture formation. Intraurethral Botulinum A toxin seems to be effective though there have been no large randomised studies comparing it against placebo. However, it is not a durable treatment option and it has not found a common place in the treatment of DSD.There is now a considerable amount of experimental data from both animal and human studies to suggest that nitric oxide (NO) is an important physiological inhibitory neurotransmitter in the urethral sphincter, mediating relaxation of the external urethral sphincter. The potential role of sphincter NO augmentation for treatment of DSD is discussed. CONCLUSION: External sphincterotomy remains the mainstay of treatment for urodynamically significant detrusor-sphincter dyssynergia, but in recent years a number of effective, alternative treatment options have become available. While at present there is no effective systemic drug treatment, recent research into external sphincter neuropharmacology suggests that systemic or topical augmentation of external sphincter NO may provide an effective method for lowering sphincter pressure.     

The self-expanding metallic ureteric stent in the long-term management of benign ureteric strictures

OBJECTIVE: To evaluate and assess the long-term complications of using the thermo-expandable, nickel-titanium alloy stent (Memokath 051, Engineers & Doctors A/S, Hornbaek, Denmark) for managing benign ureteric strictures. PATIENTS AND METHODS: Over a 3-year period, 13 Memokath stents were inserted in 11 patients (mean age 58 years, range 35-85) with 12 lower ureteric strictures. The cause of the stricture was benign in all cases, i.e. radiation fibrosis in three, retroperitoneal fibrosis, ischaemic uretero-ileal anastomosis and scarring after ureteroscopy in two each, and diathermy damage, extraluminal endometriosis and stone passage in one each. Four stents were 9 F with proximal expansion to 17 F and the other nine used were 10.5 F with proximal expansion to 20 F. The patients were followed for a mean (range) of 18 (1.5-33) months. RESULTS: No complications or side-effects occurred with nine stents; four stents were removed at a mean (range) of 16.3 (4-33) months. Three of these had become encrusted, two of which had been placed in patients who had either a history of stone disease or recurrent urinary tract infection. The other stent had migrated. CONCLUSION: The Memokath stent appears to have a useful role in managing benign ureteric strictures, but it must be closely monitored in patients who are predisposed to encrustation.     

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.     

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.     

Ease of removal of thermo-expandable prostate stents

OBJECTIVE: To report the ease of removal of the Memokath 028 prostatic stent (Engineers & Doctors A/S, Hornbaek, Denmark), an important attribute of the 'ideal' prostatic stent. PATIENTS AND METHODS: Data on patients who had had a Memokath 028 stent removed in three different centres in Europe over an 8-year period were collected retrospectively. Standardized forms were used to record relevant information from each physician's patient files. RESULTS: Ninety-three patients had their stents removed at the three reporting centres; the mean indwelling time of their stent was 12.9 months, and most stents were inserted for symptomatic benign prostate disease. Reasons for removal included recurrent outlet or storage-type urinary symptoms, migration of the stent, stent-related pain, recurrent urosepsis and detrusor failure. The stents were removed on a day-case basis in 32% of patients. Topical anaesthesia or no anaesthesia was used in 48%. Of these patients, only 9% described moderate discomfort or worse. The procedure took a mean of 11 min and was felt to be easy or fairly easy in 90% of patients. CONCLUSIONS: These data show the ease of removal of the Memokath 028 stent, reinforce its overall success in achieving the requirements of the ideal intraprostatic stent, and further emphasize the advantages of this implant over the epithelializing, permanent intraprostatic stent.     

Nickel-titanium shape memory alloy Memokath 051 ureteral stent for managing long-term ureteral obstruction: 4-year experience

PURPOSE: We present our 4-year experience with the thermo-expandable shape memory alloy Memokath 051 stent (Engineers and Doctors of Copenhagen, Copenhagen, Denmark) for managing long-term ureteral obstruction. MATERIALS AND METHODS: We used a nickel-titanium shape memory alloy ureteral stent to treat 28 patients 29 to 86 years old (mean age 59.2). Ureteral obstruction was caused by malignancy in 18 cases and by recurrent benign disease in 10. A total of 37 stents were inserted from November 1996 to November 2000 using general anesthesia. Mean followup was 19.3 months (range 3 to 35). RESULTS: Upper tract decompression was achieved in all cases. Currently 15 stents are functional in 13 patients, while 8 patients died with a total of 13 functioning stents in place. In 7 patients 9 stents were removed for various reasons. There has been no radiological evidence of encrustation to date. No patient has been rehospitalized with stent related sepsis pain or hematuria, resulting in improved quality of life. CONCLUSIONS: This stent seems to provide a significant benefit over conventional Double-J (Medical Engineering Corp., New York, New York) and other metallic stents. Its remarkable thermal memory permits removal, a feature that until recently was not available in any other metallic ureteral stent. Durable and complication-free decompression of the upper tract can be achieved with the Memokath 051.     

Thermo-expandable intraprostatic stents in bladder outlet obstruction: an 8-year study

OBJECTIVE: To assess the use of a thermo-expandable intraprostatic stent (Memokath(R), Engineers and Doctors A/S, Copenhagen, Denmark) for bladder outlet obstruction in men unable to undergo transurethral resection of the prostate (TURP), assessing symptoms, complications and duration of stent life. PATIENTS AND METHODS: The Memokath stent is a coil of a nickel-titanium alloy which has 'shape memory', the lower end expanding when heated to 55 degrees C. Risks associated with inserting the stent with a flexible cystoscope under local anaesthesia are minimal. Men were selected who were either permanently or temporarily unfit for TURP. Indications included severe respiratory and cardiovascular disease. Exclusion criteria included bladder carcinoma, calculi or detrusor failure; in all, 211 men were fitted with 217 intraprostatic stents over 8 years. RESULTS: There were 1511 TURPs during the study period; the mean age of men receiving a stent was 80.2 years, compared with 70.2 years for those undergoing TURP. The International Prostate Symptom Score decreased from a mean of 20.3 to 8.2 (P < 0.001) in the first 3 months after stent placement; there was virtually no change over 7 years. During the follow-up, 38% of men died with their stents in situ, 34% remain alive, 23% have had their stents removed for failure and 4% were removed as they were no longer required. There was a 13% migration rate and 16% repositioning rate. There were few side-effects (pain 3%, haematuria 3%, incontinence 6% and infection 6%). These frail men were more likely to die than have their stent fail. CONCLUSION: The Memokath intraprostatic stent is a valuable addition to the armamentarium of the urologist treating elderly or frail men with advanced bladder outlet obstruction and complements existing technologies.     

Effects of alpha-1-blocking agent in the treatment of detrusor sphincter dyssynergia

Effects of adrenergic alpha-1-blocking agent, prazosin, in the treatment of detrusor external-sphincter dyssynergia (DSD) were evaluated in both experimental and clinical aspects. Experimentally, in the urethral pressure profile in dogs, the maximum urethral closing pressure was depressed after intravenous injection of 1 mg prazosin. When experimental DSD was obtained in dogs by stimulating electrically the unilateral 2nd sacral root, intra-venous injection of 1 mg prazosin inhibited contraction of the external urethral sphincter. Clinically, 74 patients with DSD based on neurogenic bladder from cerebral vascular attack (CVA) (13 cases) and spinal cord injury (61 cases) were retrospectively surveyed in terms of therapeutical effects of prazosin for DSD. Spinal cord injury was subdivided to 4 groups for clinical evaluation; cervical cord injury (C) with complete paralysis, thoracic cord injury (Th) with complete paralysis, lumbar cord injury (L) with complete paralysis and spinal cord injury with incomplete paralysis. Patients with CVA and spinal cord injury with incomplete paralysis showed good response rates in subjective improvement, 69% and 60% respectively. However, those with spinal cord injury with complete paralysis showed a poor response (28% for C, 23% for Th and 14% for L). The amount of residual urine significantly decreased after treatment, in all the groups except that of lumbar cord injury with complete paralysis. In all the groups, however, even after the drug treatment the amount of residual urine ranged from 80 to 170 ml and the rates of needing clean intermittent catheterization unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)     

Experience with Memokath 051 ureteral stent

OBJECTIVE: The Memokath 051 is a thermo-expandable titanium-nickel spiral developed for long-term ureteral stenting. The aim of this study was to investigate the drainage and safety aspects of this stent. MATERIAL AND METHODS: A total of 3-4 consecutive patients were included: 22 had benign strictures, five had post-irradiation strictures and seven had malignant strictures. Follow-up visits took place after 1 month and thereafter every 3 months for at least 1 year. RESULTS: Thirty-three patients had a total of 37 stents inserted uni- or bilaterally. Pre-insertion dilatation was impossible in one patient and difficult in two, all of whom had post-irradiation strictures. Insertion was complicated in seven patients and uneventful in the other 26. Fifteen stents were in place and functioning with no discomfort or complications at death or the end of follow-up (median 14 months; range 3-30 months), while 22 were non-functioning after 1 day to 16 months (median 5 months). Of these 22 stents, 10 had migrated and 12 were malfunctioning. Among the latter, stricture length was underestimated in four patients, and the stents were replaced successfully shortly after insertion. Four stents were occluded by stones after 1-10 months. No tissue ingrowth was seen. Stent removal was easy, with the exception of one patient with stent calcification. CONCLUSIONS: The Memokath 051 is an alternative for selected patients with non-curable ureteral obstruction but is not suitable for use in patients with functional stenosis or stone formation. Insertion and removal are easy in most patients, but can be difficult or impossible, especially in patients with post-irradiation strictures and retroperitoneal fibrosis. Migration and obstruction can occur and careful follow-up is necessary.     

Urologic Aspects of Traumatic Central Cord Syndrome

ABSTRACT

Central cord syndrome (CCS) is a subset of spinal cord injury, characterized by more motor involvement of the upper extremities than the lower extremities and sacral sensory sparing. Patients with central cord syndrome have been reported to have a good rehabilitation and urologic outcome. Our purpose was to assess the urologic outcome in a group of patients with central cord syndrome.

We reviewed 23 patients with central cord syndrome who were admitted to Hines VA Hospital between 1983 and 1991, 20 of whom were older than 50 years of age. Urodynamic studies showed detrusor hyperreflexia with a synergistic EMG in 15 patients and detrusor hyperreflexia with external urethral sphincter dyssynergia (DSD) in five patients. Three patients with no urologic problems were not tested. Bladder sensation was preserved during filling in all patients. At follow-up (median = 2–4 months), 16 patients (70 percent) were voiding, seven of whom required either occasional external or intermittent catheterization; nine were voiding independently. The seven other patients (30 percent) required either continuous external or intermittent catheterization (including the five with DSD). Urologic morbidity in the period after SCI included: urinary tract infections (12), renal (2) and bladder calculi (2), superficial bladder cancer (1), epididymitis (1) and none (6). Fifteen patients (65 percent) were ambulatory at follow-up while four patients needed wheelchairs. Data were not available for the other four patients. Urodynamic studies in three of the wheelchair-bound patients showed that two of them had DSD.

Most patients with central cord syndrome have favorable urologic and rehabilitation outcomes and can be managed conservatively. A minority of such patients have DSD and they tend to have a less favorable rehabilitation and urologic outcome. A possible neuroanatomic basis for this observation is that these patients have more extensive central cord damage.     

The thermo-expandable metallic ureteric stent: an 11-year follow-up

OBJECTIVE

To review our long‐term use of the thermo‐expandable metallic ureteric stent, (model 051, PNN Medical, Denmark) for ureteric obstruction, and review current reports on its use.

PATIENTS AND METHODS

Data were collected prospectively on all patients who had a Memokath 051 ureteric stent inserted between November 1996 and November 2007. The standard stent, and wide and dual expansion versions were used. The stricture characteristics were recorded in a standard way. All stents were inserted by one surgeon in the UK and internationally, following a standard protocol.

RESULTS

In all, 74 stents were inserted into 55 patients in the study period (mean age 60 years, range 11–90). The indications for metallic stenting included primary stenting for malignancy, failed conventional open and endoscopic techniques, palliation, and where significant comorbidity limited repetitive stent changes. In 28 patients the obstruction was caused by malignancy, whereas in 27 it was caused by recurrent benign disease. The mean (range) hospital stay was 1.43 (0–7) days. Imaging after insertion showed normal or improved functional drainage in all but three patients, with immediate complications including urinary extravasation (one), poor thermo‐expansion (one) and equipment failure (locking assembly) (one). Late complications included migration (13), encrustation (two) and fungal infections (three). In all, 14 patients needed reinsertion (mean of 7.1 months, range 1–14) after insertion for migration (eight), encrustation (two), stricture progression (three) and incorrect stent length (one). Overall, 29 patients have died with the stents in‐situ. The mean (range) follow‐up was 16 (4–98) months.

CONCLUSIONS

The thermo‐expandable metallic Memokath 051 ureteric stent offers effective and durable long‐term relief from ureteric obstruction, and is a safe alternative to conventional JJ stenting. In addition there is an emerging role in palliation and the primary management of ureteric strictures.     

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.