Biomedical subjects

T B Boone

Publications and source records attributed to T B Boone.

At least 37 records · Page 2Linked to original sources

PubMed1997

The role of oxybutynin in spinal cord injured patients with indwelling catheters.

PURPOSE: The long-term benefits of oral oxybutynin in spinal cord injured patients with indwelling catheters is unknown. We reviewed our experience with this population of men and present the results of our analysis. MATERIALS AND METHODS: A total of 109 male spinal cord injured patients at the Houston Veterans Affairs Medical Center have been treated with chronic indwelling catheters (80 transurethral and 29 suprapubic). Thirty-eight patients (35%) were identified as using oxybutynin on a regular basis. These patients were compared to those not using oxybutynin with regard to urodynamic parameters and upper tract deterioration. Specifically examined were bladder compliance, bladder leak point pressure, vesicoureteral reflux, hydronephrosis, urolithiasis, febrile urinary tract infections and serum creatinine greater than 2 mg./dl. RESULTS: The mean duration of indwelling catheter use was 11.9 years (12.4 without oxybutynin and 10.9 on oral oxybutynin). Of the 31 patients with normal compliance (greater than 20 ml./cm. water), 24 (77%) were using oxybutynin (p = 0.001). Bladder leak point pressures were abnormal (greater than 35 cm. water) in 5 of 32 patients (16%) on oxybutynin versus 34 of 60 (57%) without it (p <0.001). Hydronephrosis was present in 15 of 66 patients (23%) without oxybutynin versus 1 of 36 (3%) with oxybutynin (p = 0.009). Febrile urinary tract infections occurred in 4 of 35 patients (11%) versus 17 of 62 patients (27%) with or without oxybutynin, respectively (p = 0.077). No significant differences were found between the 2 groups with regard to reflux, renal scars, stones or elevated serum creatinine. CONCLUSIONS: It appears that regular use of oxybutynin may be beneficial in spinal cord injured patients who require chronic indwelling catheters for bladder management. Our analysis reveals that patients who take oxybutynin regularly have better bladder compliance, lower bladder leak point pressures and less hydronephrosis. Until a prospective, randomized trial reveals contradicting outcomes, empiric use of oxybutynin in all spinal cord injured patients requiring chronic indwelling catheters seems justified.

Adult↗

PubMed1997

Ileovesicostomy as an alternative form of bladder management in tetraplegic patients.

OBJECTIVES: Bladder management in tetraplegic patients traditionally has been intermittent catheterization by a caretaker, placement of indwelling suprapubic or urethral catheters, sphincterotomy and external catheter drainage, or supravesical urinary diversion with an ileal conduit. The aim of this study was to examine the ileovesicostomy as an alternative form of bladder management in such patients. METHODS: We report our experience with ileovesicostomy as an incontinent cutaneous urinary diversion not requiring ureteral reimplantation. Six tetraplegic patients who had experienced significant morbidity with their preoperative form of bladder management were managed with an ileovesicostomy fashioned like a funnel from the bladder dome to the right lower quadrant. All patients underwent preoperative and postoperative fluoroscopic and urodynamic evaluations. Patients were evaluated preoperatively and followed postoperatively with serum chemistries, upper urinary tract imaging, and urine bacteriologic studies. RESULTS: There were no perioperative complications. Postoperative urodynamics demonstrated subjects to have a mean stomal leak-point pressure of 7.7 cm H2O (range 5 to 10). Radiographically, patients carried low urinary residuals (less than 100 cc) and did not exhibit vesicoureteral reflux. In follow-up of 12 to 15 months, no patient has demonstrated calculus formation, hydronephrosis, autonomic dysreflexia, or worsening renal function. CONCLUSIONS: This procedure successfully creates continuous urinary drainage without catheterization, while maintaining the native antireflux mechanism of the ureterovesical junction and avoiding indwelling foreign materials in the urinary tract. Longer follow-up with more cases will be necessary to confirm these findings and to support a recommendation of the incontinent ileovesicostomy as a standard method for managing the neurogenic bladder in tetraplegic patients.

Adult↗

PubMed1997

Correlation of urodynamic results and urethral coaptation with success after transurethral collagen injection.

OBJECTIVES: We correlated preoperative urodynamic and intraoperative endoscopic findings with initial improvement, single collagen injection effectiveness for intrinsic sphincter deficiency (ISD), and long-term improvement following transurethral collagen injection for stress urinary incontinence (SUI). METHODS: Since 1993, 79 patients have been treated with transurethral collagen injection by the same urologist. Of these patients, intraoperative photographs of urothelial coaptation immediately after injection were available in 67 patients: 35 women with ISD, 24 men with incontinence, primarily following prostatectomy, and 8 children with neurogenic bladder. Urothelial coaptation was described as snug, fair, or poor. Preoperative Valsalva leak point pressure (VLPP), detrusor instability, impaired bladder compliance, bladder neck appearance, urothelial scarring, and degree of coaptation were correlated with both initial and long-term improvement. Initial improvement was compared with long-term improvement. RESULTS: Initial improvement was experienced by 85% of all the subjects (86%) of the women, 80% of the men, and 100% of the children with a neurogenic bladder condition). Overall, 31% of patients had long-term improvement after a mean follow-up of 2.2 years, including 43% of the women, 13% of the men, and 33% of the children. The patients underwent a mean of 1.5 (1 to 4) collagen injections. There was a significant correlation between degree of coaptation and initial improvement (P = 0.003), but not with long-term improvement. There was no correlation between VLPP detrusor instability, impaired compliance, bladder neck appearance, or urethral scarring and initial improvement. There was no correlation between any parameter and long-term improvement or between initial and long-term improvement. CONCLUSIONS: Initial endoscopic appearance following collagen injection predicted initial, but not long-term, improvement after one collagen injection. Initial improvement was high in both men and women but decreased considerably over time, more so in men, and was not significantly correlated with long-term success. Urodynamic and endoscopic findings do not predict long-term success following collagen injection.

Adaptation, Physiological↗

PubMed1996

Urodynamics and multiple sclerosis.

Multiple sclerosis is an enigmatic and devastating neurologic disease. Voiding dysfunction is common and the irritative and obstructive symptoms can be disabling to the patient. Voiding symptoms alone are unreliable predictors of bladder and urethral dysfunction secondary to multiple sclerosis. This article focuses on the central role played by urodynamic studies in the initial assessment and management of the lower urinary tract. Detrusor hyperreflexia is the most common urodynamic finding. However, a variety of urodynamic patterns can be seen and voiding function may change over time with this chronic neurologic disorder.

Humans↗

PubMed1996

Peripheral neuropathy and peripheral nerve injury.

The peripheral nerves to the bladder can be altered by several disease processes. Voiding symptoms alone are not reliable in predicting the exact neurogenic bladder dysfunction. Urodynamic evaluation is crucial to optimize therapy and to rule out concomitant pathology.

Diabetes Complications↗

PubMed1996

Risk factors for urinary incontinence after radical prostatectomy.

PURPOSE: We identified risk factors associated with urinary incontinence after radical retropubic prostatectomy. MATERIALS AND METHODS: The time from operation until urinary continence was achieved was determined by chart review and questionnaire in 581 patients who were continent before undergoing radical retropubic prostatectomy between 1983 and 1994. Using univariate and multivariate analyses of data gathered prospectively, we examined risk factors associated with incontinence in these patients. RESULTS: The actuarial rate of urinary continence at 24 months was 91% for the entire patient population and 95% for those treated after 1990. Many factors were associated with the risk of incontinence in univariate Cox proportional hazards regression analysis (patient age and weight, degree of obstructive voiding symptoms, prior transurethral resection of the prostate, clinical stage, intraoperative blood loss, resection of neurovascular bundles, postoperative anastomotic stricture and technique of vesicourethral anastomosis). However, in a multivariate analysis the factors that were independently associated with increased chance of regaining continence were decreasing age, a modification in the technique of anastomosis (introduced in 1990), preservation of both neurovascular bundles and absence of an anastomotic stricture. With introduction of the new surgical technique in 1990 the median time to continence decreased from 5.6 to 1.5 months and the rate of continence at 24 months increased from 82 to 95%. CONCLUSIONS: While the risk of urinary incontinence after radical prostatectomy is related to the uncontrollable factor of patient age, it is also sensitive to the surgical technique used.

Actuarial Analysis↗

PubMed1995

Lower pole calicostomy for the management of iatrogenic ureteropelvic junction obstruction.

It is often possible to use endoscopic techniques for the management of iatrogenic upper ureteral or ureteropelvic junction obstruction. However, in some cases with severe stricture disease or significant ischemic injury open surgical reconstruction is necessary. We report our experience with ileal ureter-lower pole calicostomy for the management of these complex urological injuries. During the last 3 years we treated 3 patients with severe ureteral/ureteropelvic junction obstruction secondary to iatrogenic injuries, including ureteral avulsion during ureteroscopic stone extraction, ureteral laceration during dilation for diagnostic ureteropyeloscopy, and ureteral ligation with ureteropelvic junction disruption and large peri-pelvic urinoma. In all cases unsuccessful attempts at endoscopic management necessitated open repair. Lower pole heminephrectomy was performed in all patients to expose the lower pole calix and ileal ureter-lower pole calicostomy was created due to the injury of large segments of the ureter. Satisfactory results were demonstrated on postoperative excretory urography and by a lack of symptoms. Followup averaged 23 months (range 20 to 26) with stable renal function in all patients. We believe that ileal ureter-lower pole calicostomy represents an attractive alternative for the management of severe ischemic, iatrogenic upper ureteral or ureteropelvic junction obstruction when endoscopic maneuvers are not possible or ineffective.

Adult↗

PubMed1994

Multicenter trial in North America of UroLume urinary sphincter prosthesis.

We investigated the effectiveness and associated complications of treatment with an endoluminal urethral sphincter prosthesis in 153 spinal cord injury men (mean age 36 years, range 16 to 74 years) with urodynamically diagnosed detrusor-external sphincter dyssynergia. These patients were prospectively treated with a urethral sphincter stent at 15 centers in North America. Followup ranged from 2 to 33 months. Voiding pressures averaged 76 +/- 28, 42 +/- 21, 44 +/- 38, 35 +/- 18 and 32 +/- 20 cm. water, respectively, before prosthesis insertion in 153 patients and at 3 months in 123, 6 months in 114, 12 months in 98 and 24 months in 22. A significant decrease in voiding pressure was noted in the 22 patients at 24 months compared with matched preoperative data (80 +/- 25 cm. water, p = 0.03). The residual urine decreased from 181 +/- 154 ml. before insertion to 82 +/- 93 ml. at 24 months (p = 0.01). Maximum cystometric capacity remained constant, with a mean of 195 +/- 158 ml. before insertion to 248 +/- 122 ml. at 24 months (p = 0.17). No significant differences were apparent after 24 months of followup in any of the urodynamic parameters between 44 patients with and 109 without previous external sphincterotomy. Hemorrhage requiring blood transfusion, obstructive hyperplastic epithelial overgrowth and soft tissue erosion did not occur. No deleterious effects were observed on renal or erectile function. Of the patients 43 (28.1%) required 2 prostheses to bridge the external sphincter completely. Stent removal was required in 10 patients. Seven explantations were required for prosthesis migration, 1 for pain and urethral edema, 1 for inability to maintain a condom catheter, and 1 for nonepithelialization and secondary bladder neck obstruction. A total of 13 patients (8.5%) required a subsequent operation for bladder neck obstruction. Therefore, the sphincter prosthesis is an attractive modality for the treatment of external sphincter dyssynergia in patients with and without previous external sphincterotomy because of its ease of deployment and minimal associated morbidity.

Adolescent↗

PubMed1994

Flutamide-induced testicular undescent in the rat is associated with alterations in genitofemoral nerve morphology.

Androgen regulation of testicular descent is an established fact. However, the mechanisms by which androgens assert their influence is unknown. One of the leading hypotheses regarding androgenic control of testicular descent is based upon the assumption that testosterone regulates the development of the sexually dimorphic genitofemoral nucleus and nerve (GFN). To investigate whether or not alterations in the genitofemoral nerve are indeed androgen dependent and associated with testicular undescent, we administered flutamide in a time-specific manner to pregnant Sprague-Dawley rats. The GFN of ten animals with unilateral intra-abdominal testicular undescent was compared with the contralateral GFN associated with the descended testicle. Digital microscopic evaluations found that the GFN associated with testicular undescent did express altered morphologic abnormalities. Specifically, the GFN associated with the cryptorchid testicle had significant reductions in the neural diameter (.0169 +/- .0024 mm.2 versus .0275 +/- .0079 mm.2; p < .01), the number of large myelinated fibers per mm.2 (8.4 +/- 3.3 versus 18.8 +/- 5; p < .001) and the number of small myelinated nerve fibers per mm.2 (632 +/- 87.4 versus 1090.7 +/- 104.3; p < .001). These data suggest that testicular undescent in the rat is associated with morphologic alterations in the ipsilateral genitofemoral nerve. The exact mechanism of how these alterations are related to cryptorchidism remains to be elucidated.

Age Factors↗

PubMed1993

Ureteropelvic junction disruption following blunt abdominal trauma.

Disruptions of the ureteropelvic junction following blunt abdominal trauma are rare. Our recent management of 8 cases (7 patients) revealed that an immediate diagnosis of this entity was made in less than 50% of the patients. The majority of delayed diagnoses occurred when the patients experienced absence of hematuria associated with nonresponsive hypovolemic shock. The clinical instability of the patients required emergency celiotomy for stabilization and precluded our obtaining appropriate contrast enhanced radiographic studies. Retroperitoneal findings at operation failed to reveal evidence of a perinephric hematoma. The kidneys were palpably normal and, therefore, they were not directly examined. Despite these negative retroperitoneal findings the patients sustained disruption of the ureteropelvic junction. Therefore, we stress that a negative exploratory laparotomy without direct visualization of the kidney should not exclude radiographic evaluations for retroperitoneal injuries.

Abdominal Injuries↗

PubMed1993

Management of low velocity gunshot wounds to the anterior urethra: the role of primary repair versus urinary diversion alone.

The management of partial transection of the anterior urethra following penetrating penile injuries is controversial. Optional therapeutic techniques range from a primary sutured reapproximation to urinary diversion alone. We recently managed 17 low velocity gunshot wounds to the external genitalia in which the missile traversed the penile corpus cavernosum, and was associated with less than 40% transection of the corpus spongiosum and anterior urethra. Nine patients were managed with suprapubic diversion, skin débridement and corporeal closure along with placement of a urethral catheter. Eight patients were managed by suprapubic diversion, débridement, closure of the corporeal bodies and a primary sutured reapproximation of the anterior urethra. Urethral strictures developed in 7 patients (78%) managed by a suprapubic tube and urethral stenting during an average followup of 20 months (range 18 to 24). In contrast, 1 patient (12%) managed by a sutured urethral approximation had a urethral stricture during an average followup of 20 months (range 18 to 30, p < 0.01). Our data support a significantly better prognosis for partial transection of the anterior urethra secondary to low velocity gunshot wounds if managed by aggressive wound débridement, corporeal repair, placement of a suprapubic catheter and primary repair of the urethra.

Humans↗

PubMed1993

Major renal lacerations with a devitalized fragment following blunt abdominal trauma: a comparison between nonoperative (expectant) versus surgical management.

Of 43 patients who sustained blunt trauma resulting in a major renal laceration with a devitalized fragment 27 had coexisting intraperitoneal and renal injuries for which emergency celiotomy and repair of the nonurological trauma were done. Management of the renal injuries consisted of simultaneous renal exploration with 23% urological morbidity in 13 cases or expectant management with 85% urological morbidity in 14 cases. In this latter patient population infected urinomas and perinephric abscesses seeded from coexisting enteric or pancreatic injuries were the most common complication (57%). The remaining 16 of the 43 patients sustained renal lacerations without associated intraperitoneal injuries and all were managed expectantly with 38% urological morbidity. These findings suggest that renal exploration and surgical repair significantly improve the prognosis only in patients with simultaneous intraperitoneal and renal injuries (p < 0.01).

Abdominal Injuries↗

PubMed1992

Transurethral intravesical electrotherapy for neurogenic bladder dysfunction in children with myelodysplasia: a prospective, randomized clinical trial.

Myelomeningocele is the most common cause of neurogenic bladder dysfunction in children. Urinary incontinence is socially disabling for many of these children and undetected elevations in detrusor pressure can lead to serious upper tract damage. Sensory receptors in the bladder mucosa and submucosa provide afferent information to the central nervous system regulating the micturition reflex. Since 1959 Katona and several other investigators have used intravesical electrotherapy for diagnosis and treatment of the neuropathic bladder. Our objective was to conduct a randomized, sham controlled and blinded clinical study on the efficacy of transurethral intravesical electrotherapy in treating urinary incontinence in the myelodysplastic child. A total of 36 children was enrolled in the study and 31 completed the entire protocol. Of the patients completing the study 13 were randomly selected to serve as an internal sham control having the electrocatheter placed without activating the stimulator. These patients were subsequently treated with a 3-week course of electrotherapy. The remaining 18 patients completing the study were randomly selected to undergo 2, 3-week courses of intravesical bladder stimulation. Urodynamic studies were performed before and after each treatment series. Detailed daily questionnaires were submitted to each participant covering subjective improvement in urinary continence and any development of bladder sensory awareness. Analysis of the urodynamic data and questionnaires failed to reveal any statistically significant increase in bladder capacity, development of detrusor contractions, improvement in detrusor compliance or the acquisition of bladder sensation allowing timely intermittent catheterization preventing urinary incontinence.

Child↗

PubMed1992

Postpubertal genitourinary function following posterior urethral disruptions in children.

A total of 24 boys sustaining a simultaneous pelvic fracture and posterior urethral disruption was observed from the time of injury through puberty. Average length of followup was 6 years. In contrast to the adult, in whom the urethra is invariably injured at the prostatomembranous junction, the posterior urethral disruptions in the prepubertal patient were at 3 distinct locations: 1) supraprostatic in 4 patients, 2) transprostatic in 4 and 3) prostatomembranous in 16. Prolonged followup through puberty in these children revealed that the frequency of complications was significantly higher for urethral injuries proximal to the prostatomembranous region compared to those at this latter site: impotence 75% versus 31%, intractable strictures following repairs 75% versus 12% and urinary incontinence 25% versus 0%. In summary, the prognosis of children who sustain a posterior urethral disruption should be based on the location of the injury and must remain guarded until the individual attains a postpubertal status.

Adolescent↗

PubMed1992

Unilateral post-obstructive diuresis in the neonate.

A total of 3 neonates exhibited severe post-obstructive diuresis after relief of unilateral ureteral obstruction. Of the neonates 2 had normal kidneys contralaterally while 1 had a contralateral kidney that was dysplastic. Urinary output exceeded oral intake initially in all 3 patients necessitating intravenous supplementation for up to 10 days. Stabilization resulted from an increase in oral intake rather than a decrease in diuresis. Unilateral post-obstructive diuresis is extremely uncommon but it may occur in the neonate because of the unique features of the renal physiology encountered in this age patient.

Diuresis↗

PubMed1990

Prostatomembranous urethral disruptions: management by suprapubic cystostomy and delayed urethroplasty.

Management of prostatomembranous urethral disruptions associated with pelvic fractures remains a major controversy in urology. A group of 64 patients who suffered a prostatomembranous urethral disruption in association with a pelvic fracture and who were managed initially by suprapubic cystostomy with delayed urethroplasty was compared to 17 patients managed initially by primary realignment. No statistically significant difference in the incidence of impotence or urinary incontinence was found between the 2 groups (p greater than 0.5) Secondary reconstructions for impassable strictures developed in 95% of the patients treated by a suprapubic tube alone compared to 53% of those treated by primary realignment. Indeed, only 1 patient in the latter group achieved urethral continuity that did not require further intervention. We conclude that while primary realignment is associated with no increase in the instance of impotence and urinary incontinence, it subjects the patient to a major operation at a critical time and provides little in the way of long-term positive gains for the effort expended. In the final analysis the outcome is more dependent upon the nature of the injury and the quality of the repair than upon the order in which the repair is effected.

Cystostomy↗

PubMed1985

Organization of projections from the principal sensory trigeminal nucleus to the hypoglossal nucleus in the rat: an experimental light and electron microscopic study with axonal tracer techniques.

The organization of projections from the principal sensory trigeminal nucleus (PSN) to the hypoglossal nucleus (XII) in the rat was investigated at the light and electron microscopic level with retrograde and anterograde axonal tracer techniques. Microiontophoretic injection of horseradish peroxidase (HRP) into XII resulted in retrograde labeling of neurons confined to the dorsal one-third of the PSN. Labeled neurons were found bilaterally, although a clear preponderance for ipsilateral distribution was evident. Most labeled neurons were found in the medial one-third and caudal two-thirds of the PSN. Labeled neurons were large (30-50 micron), round-to-pear shaped multipolar cells with dendrites oriented primarily in the mediolateral direction. At the electron microscopic level, HRP reaction product was found throughout the cytoplasm of soma and processes of PSN projection neurons. The ultrastructural characteristics of these cells included a round, centrally placed nucleus and invaginated nuclear envelope, sparse Nissl bodies, numerous free ribosomes, mitochondria, lysosomes and Golgi complexes. Three to four main stem dendrites gradually tapered from the cell body and numerous synaptic terminals impinged upon soma and dendrites of labeled PSN neurons. Microiontophoretic injection of tritiated amino acids or HRP into the dorsal one-third of the PSN resulted in moderately dense terminal labeling in XII bilaterally, although mainly ipsilaterally. Terminal labeling was found diffusely throughout all regions of XII. Fibers descended the brainstem in the dorsolateral reticular formation and entered XII ventrolaterally. At the electron microscopic level, boutons containing HRP reaction product were found to synapse on dendritic processes in XII. Labeled boutons were characterized by clear, spherical vesicles and an asymmetrical postsynaptic density. The significance of these results are discussed in relation to oro-lingual motor behavior.

Animals↗

PubMed1984

A combined flat-embedding, HRP histochemical method for correlative light and electron microscopic study of single neurons.

A simple and reproducible method is described for studying the morphology of the same neuron at the light and electron microscopic level. This method utilizes horseradish peroxidase histochemistry and a recently described flat-embedding procedure wherein thin, aldehyde-fixed sections are placed in resin between glass microscope slides pretreated with dimethyldichlorosilane. The significance of these combined methodologies for correlative light and electron microscopic studies of single neurons is discussed.

Animals↗