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Biomedical subjects

M B Chancellor

Publications and source records attributed to M B Chancellor.

At least 55 records · Page 3Linked to original sources
PubMed2001

Future trends in the treatment of urinary incontinence.

Anticholinergic drugs act on efferent nerves to counteract overactive bladder (OAB) after it occurs. To prevent the occurrence of OAB, therapies should be directed at blocking the afferent nerves that control the bladder. Tachykinin-receptor antagonists hold great promise in this regard, since they can be administered orally and do not increase the risk of urinary retention that occurs with anticholinergics. Advanced drug delivery systems, such as controlled-release oral oxybutynin (oxybutynin-XL) can reduce the incidence of anticholinergic side effects. In a similar manner intravesical therapy for OAB is site specific, and thus also reduces the occurrence of adverse events. Moreover, the difficulties of intravesical therapy may now be overcome with advanced delivery techniques such as an implantable, long-acting drug-delivery pump. Another intravesical therapy that has met with great acceptance and success is the administration of chili pepper extracts, especially resiniferitoxin, which may be effective for up to 3 months with one application. Finally, gene therapy holds great promise for OAB, because it is possible to access all of the genitourinary organs via endoscopy and other minimally invasive techniques that are ideally suited for gene therapy.

Journal Article↗
PubMed2000

Reliability of color Doppler ultrasound urodynamics in the evaluation of bladder outlet obstruction.

OBJECTIVES: To analyze the intrarater and interrater reliability of a newly developed noninvasive urodynamic technique based on color Doppler ultrasound for the evaluation of bladder outlet obstruction. We previously demonstrated the feasibility of this new technique. METHODS: Color Doppler ultrasound urodynamic evaluations were performed on 31 men with and without bladder outlet obstruction. An ultrasound image-directed Doppler system with a 3.75-MHz probe operated by a remote control robotic manipulator was used to obtain color scale data using the transperineal approach in men during voiding. We measured the flow velocities in the distal prostatic (V1) and membranous urethra (V2) and used them to obtain the velocity ratio (VR = V1/V2). Combining this information with simultaneous uroflowmetry, the functional cross-sectional area of the distal prostatic urethra (A1) was calculated. These parameters were independently reinterpreted by an inexperienced investigator using the color image data stored in a personal computer. The intrarater and interrater reliability for VR were assessed using a classification based on cutoff values previously shown to indicate the presence or absence of obstruction. RESULTS: The retest correlation using Spearman's rho for VR in terms of intrarater and interrater reliability was 0.95 and 0.57, respectively; that for A1 was 0.97 and 0.64, respectively. Using a VR of less than 1.1 (to indicate the absence of obstruction) and a VR greater than 1.6 (to indicate the presence of obstruction) for classification, intrarater and interrater agreement occurred in 93.6% to 96.8% and 77.4% to 83. 9% of cases, respectively. CONCLUSIONS: The color Doppler ultrasound urodynamic technique for noninvasive evaluation of bladder outlet obstruction can be performed with reasonable reliability.

Adult↗
PubMed2000

Noninvasive urodynamic evaluation of bladder outlet obstruction using Doppler ultrasonography.

OBJECTIVES: Previously we had developed a new method of noninvasive urodynamics using color Doppler ultrasound. Using this technique, we attempted to identify parameters that would diagnose bladder outlet obstruction (BOO). METHODS: Twenty-two men who underwent pressure-flow urodynamic studies were included. Color scale transperineal ultrasound and uroflowmetry data were analyzed by custom-made software. The maximum flow velocities in the entire prostatic urethra (V(0)), in the distal prostatic urethra just proximal to the external urethral sphincter (V(1)), and in the membranous urethra (V(2)) were obtained. Corresponding functional cross-sectional areas of the urethra at these three sites (A(0), A(1), and A(2)) were calculated as Qmax/V. The velocity ratio (VR), which was equal to V(1)/V(2), was also calculated as a parameter. All these parameters obtained by the velocity-flow urodynamics were compared with the Abrams-Griffiths number (AG). RESULTS: From the x-y plots obtained, VR correlated best with AG, with Spearman's rho of 0. 728. A(0) and A(1) had rho values of -0.461 and -0.708 against AG, respectively. All men with VR exceeding 1.6 had obstruction, whereas those with VR less than 1.1 did not. CONCLUSIONS: The VR was found to be the best parameter for diagnosing BOO. When prostatic urethral obstruction was present, the velocity in the prostatic urethra would be high but the velocity slows down to 62.5% or greater immediately below the sphincter. We believe that noninvasive pressure-flow-like urodynamic evaluation based on Doppler ultrasound has clear potential for diagnosing BOO.

Humans↗
PubMed2000

Metastatic osteomyelitis after pubovaginal sling using bone anchors.

We report a case of osteomyelitis with metastasis to the T10 vertebra related to bone anchor use with pubovaginal sling. The morbidity was significant: long-term intravenous antibiotics, multiple surgeries to correct the problem, and subsequent chronic pelvic pain. Given that this complication is unheard of after standard fascia or allograft sling, consideration should be given before bone anchor use in women at risk for wound infection (diabetes, obesity, or reoperation). Minimally, patients should be told of the possibility of this severe complication in the informed consent with bone anchor use.

Adult↗
PubMed2000

Preliminary results of myoblast injection into the urethra and bladder wall: a possible method for the treatment of stress urinary incontinence and impaired detrusor contractility.

The purpose of this study is to explore the feasibility of myoblasts, the precursors of muscle fibers, injected periurethrally as a potential treatment of stress urinary incontinence. We also studied myoblast injection into the bladder wall to potentially improve detrusor contractility. A myoblast cell line was transduced with adenovirus carrying the expression of the beta-galactosidase reporter gene while in culture. The cells were incubated with fluorescent latex microspheres (FLMs) to follow the outcome of the injected cells. The tissue was harvested 3-4 days after injection; sectioned, fixed, assayed for beta-galactosidase expression, and counterstained with H+E. Photographs of the slides were taken under light and fluorescence microscopy. We have noted a large number of cells expressing beta-galactosidase and containing FLMs in the urethral and bladder walls under fluorescent microscopy (8 animals). Many regenerative myofibers expressing beta-galactosidase were also seen in the urethral and bladder walls. The fusion of injected myoblasts to form myotubes was seen in both the urethral and bladder walls. The introduction of myoblasts into the urethral and bladder wall is feasible and results in formation of myotubes and myofibers in the smooth muscle layers of the lower urinary tract. We hypothesize that myoblast injections can be used as a non-allergenic agent to enhance urethral closure and bladder function.

Animals↗
PubMed2000

Myoblast therapy for stress urinary incontinence and bladder dysfunction.

The field of tissue engineering and gene therapy has an exciting and promising future. During the past few years we have begun a comprehensive effort to investigate the use of myoblasts to improve and expand the treatment of stress urinary incontinence and bladder dysfunction. Moreover, we can expect the application of myoblast-mediated ex vivo gene transfer in the field of urology. In this paper we discuss the compositions of and methods involving the use of myogenic or muscle-derived cells for tissue engineering and cell-mediated gene therapy.

Cell Transplantation↗
PubMed2000

Removal of UroLume endoprosthesis: experience of the North American Study Group for detrusor-sphincter dyssynergia application.

PURPOSE: We present the experience of the North American UroLume Multicenter Study Group with removal of the UroLume endoprosthesis. MATERIALS AND METHODS: A total of 160 neurologically impaired patients were enrolled in the North American UroLume Multicenter Study Group for detrusor external sphincter dyssynergia application. Analysis was performed in 2 groups of patients in which the device was removed during insertion and after implantation, respectively. RESULTS: Device retrieval was required during insertion in 21 patients (13%) mainly due to misplacement or migration in 17. Extraction was done with minimal complications and in all but 2 cases subsequent UroLume implantation was successful. Of 158 men with the device in place 31 (19.6%) required removal. In 34 procedures 44 devices were removed, mainly due to migration. Time from implantation to removal ranged from 4 days to 66 months (mean 22 months). The UroLume was removed en bloc in 20 cases and in parts or wire by wire in 19. The majority of patients had no or minimal complications after extraction. Only 2 patients had serious temporary complications, including bleeding and urethral injury, with no lasting consequences. No malignancy developed as a result of UroLume insertion. CONCLUSIONS: While there is a potential for urethral injury and bleeding, UroLume endoprosthesis removal is largely a simple procedure with minimal complications and consequences.

Humans↗
PubMed2000

Urolume stent placement for the treatment of postbrachytherapy bladder outlet obstruction.

OBJECTIVES: Transurethral resection (TURP) or incision of the prostate is generally not effective for treating bladder outlet obstruction after transperineal brachytherapy for prostate cancer. Furthermore, TURP could compromise full-dose effective radiation delivery to the prostate. We analyzed the efficacy of the UroLume stent in treating the urinary outflow obstruction in such patients. METHODS: Five patients who had undergone brachytherapy (3 with (192)Ir high-dose radiation and 2 with (125)I) subsequently developed one or more episodes of urinary retention 2 weeks to 4 years after treatment. The patients failed or could not tolerate alpha-blockers or clean intermittent catheterization. Three patients subsequently underwent urethral dilation/optical internal urethrotomy for strictures, and 1 patient underwent suprapubic tube placement. Following the failure of these interventions, each of these patients had a UroLume stent placement. A single UroLume stent (2 cm in 3 patients and 2.5 cm in 2 patients) was placed under local/spinal anesthesia. RESULTS: All patients were able to void spontaneously immediately after stent placement. Of the patients with previous urethral strictures, 1 remained continent and 1 had persistent incontinence. Neither of the patients with early postbrachytherapy retention developed incontinence after stent placement. The main complaints following stent placement were referred pain to the head of the penis and dysuria. Stent-related symptoms necessitated stent removal in 2 of 5 patients, 4 to 6 weeks after placement. CONCLUSIONS: The UroLume stent can be used as an alternative form of therapy for managing postbrachytherapy bladder outlet obstruction. The treatment is easily reversible by removing the stent when obstruction resolves.

Aged↗
PubMed2000

Long-term results of augmentation cystoplasty in spinal cord injury patients.

STUDY DESIGN: Prospective monocentric follow-up study. OBJECTIVES: To assess long-term functional and urodynamic results of augmentation enterocystoplasty in spinal cord injury (SCI) patients with detrusor hyperreflexia and reflex incontinence who failed to respond to conservative treatment. SETTINGS: Department of Urology (Pitié-Salpétrière Hospital, Paris, France), Department of Neurological Rehabilitation (Raymond Poincaré Hospital, Garches, France), Assistance Publique - Hopitaux de Paris, University Paris VI and V, France. METHODS: Prospective study of 17 SCI patients (four above T6 level, nine between T6 and T12, and four below T12) with history of refractory urge incontinence to pharmacotherapy. Partial cystectomy (subtrigonal for 15) was performed with Hautmann enterocystoplasty (15) or detubularized clam cystoplasty (two). RESULTS: Mean follow-up was 6.3+/-3.8 years (range 1.25 - 10.5 years). Fifteen of 17 (88.5%) patients were completely continent under self clean intermittent catheterization (CIC) (mean 4.6/day, range 4 - 7). The remaining two patients with pudendal nerve denervation had persistent stress urinary incontinence. No operative complications were noted. Long-term complications included recurrent pyelonephritis for one patient. Maximal cystometric capacity increased from 174.1+/-103.9 to 508.1+/-215.8 ml (P<0.05). Maximal end filling pressure decreased from 65.5+/-50.2 to 18.3+/-7.9 cm H2O (P<0.05). CONCLUSION: Urodynamic evaluation and clinical assessment demonstrate long-term success of augmentation enterocystoplasty in an homogeneous population (SCI) without delayed complications in SCI patients.

Adult↗
PubMed2000

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.

Adult↗
PubMed2000

Intravesical neuromodulatory drugs: capsaicin and resiniferatoxin to treat the overactive bladder.

Current pharmacologic treatment of the overactive bladder relies on anticholinergic drugs. However, these drugs often have troublesome side effects and frequently are given in doses insufficient to restore continence in patients with detrusor instability. We present the background and basic and clinical research dealing with intravesical instillation of capsaicin and resinfferatoxin as treatments for the overactive bladder. Capsaicin is the main pungent ingredient in "hot" peppers of the genus Capsicum. It is a specific neurotoxin that desensitizes C-fiber afferent neurons, which may be responsible for the signals that trigger detrusor overactivity. Studies with capsaicin over the past 8 years have demonstrated clinical efficacy with minimal long-term complications. Most of these studies have also shown that the acute pain and irritation associated with capsaicin are a major deterrent to widespread use. Resiniferatoxin (RTX), an ultrapotent analog of capsaicin that appears to have similar efficacy but with much less acute side effects may be more useful. Intravesical instillation of capsaicin or resiniferatoxin is a promising treatment for the overactive bladder.

Administration, Intravesical↗
PubMed2000

Transverse retubularized ileovesicostomy continent urinary diversion to the umbilicus.

The transverse retubularized ileovesicostomy is useful as a continent urinary diversion when the appendix is unusable or unavailable for an appendicovesicostomy continent urinary diversion. Eight patients (mean age 29 years) with difficulty catheterizing their native urethras underwent creation of a transverse retubularized ileovesicostomy continent urinary diversion to the umbilicus. Diagnoses included myelomeningocele (3), multiple sclerosis (1), and spinal cord injury (4). Concomitant procedures included ileocystoplasty, antegrade continence enema procedure, and pubovaginal sling. All patients were able to catheterize their ileovesicostomy conduit and stoma easily with a 14F catheter. Six patients were completely dry, and two patients needed to catheterize every 3 to 4 hours to prevent urinary leakage. Mean follow-up was 3 years. Experience with the transverse retubularized ileovesicostomy continent urinary diversion to the umbilicus has been favorable. When the Mitrofanoff appendicovesicostomy continent urinary diversion is not an option, the transverse retubularized ileovesicostomy has several advantages as a second choice.

Adolescent↗
PubMed2000

Long-term results of sacral nerve stimulation (S3) for the treatment of neurogenic refractory urge incontinence related to detrusor hyperreflexia.

PURPOSE: We assess clinical and urodynamic results of sacral nerve stimulation for patients with neurogenic (spinal cord diseases) urge incontinence and detrusor hyperreflexia resistant to parasympatholytic drugs. MATERIALS AND METHODS: Since 1992, 9 women with a mean age of 42.6 years (range 26 to 53) were treated for refractory neurogenic urge incontinence with sacral nerve stimulation. Neurological spinal diseases included viral and vascular myelitis in 1 patient each, multiple sclerosis in 5 and traumatic spinal cord injury in 2. Mean time since neurological diagnosis was 12 years. All patients had incontinence with chronic pad use related to detrusor hyperreflexia. Intermittent self-catheterization for external detrusor-sphincter dyssynergia was used by 5 patients. Social life was impaired and these patients were candidates for bladder augmentation. A sacral (S3) lead was surgically implanted and connected to a subcutaneous neurostimulator after a positive test stimulation trial. RESULTS: Mean followup was 43.6 months (range 7 to 72). All patients had clinically significant improvement of incontinence, and 5 were completely dry. Average number of voids per day decreased from 16.1 to 8.2. Urodynamic parameters at 6 months after implant improved significantly from baseline, including maximum bladder capacity from 244 to 377 ml. and volume at first uninhibited contraction from 214 to 340 ml. Maximum detrusor pressure at first uninhibited contraction increased in 3, stabilized in 2 and decreased in 4 patients. Urodynamic results returned to baseline when stimulation was inactivated. All patients subjectively reported improved visual analog scale results by at least 75% at last followup. CONCLUSIONS: Sacral nerve stimulation can be used as a reversible treatment option for refractory urge incontinence related to detrusor hyperreflexia in select patients with spinal lesions.

Adult↗