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P D Ramsden

Publications and source records attributed to P D Ramsden.

At least 19 recordsLinked to original sources
PubMed2003

Noninvasive measurement of bladder pressure. Does mechanical interruption of the urinary stream inhibit detrusor contraction?

PURPOSE: As part of developing a noninvasive method to measure bladder pressure using an inflatable penile cuff, we tested the hypothesis that detrusor contraction is maintained without inhibition during the test. MATERIALS AND METHODS: Five healthy volunteers and 26 male patients with lower urinary tract symptoms underwent interruption of established urine flow by controlled inflation of a cuff placed around the penis with simultaneous invasive bladder pressure monitoring. After interruption of flow the cuff was rapidly deflated and voiding was allowed to resume. The bladder pressure was recorded before, during and after interruption of flow by cuff inflation. RESULTS: During flow interruption an isovolumetric increase in detrusor pressure was observed. When the cuff was deflated the detrusor pressure quickly returned to preinflation values and urine flow immediately resumed. Intra-abdominal pressure did not change during the cuff inflation cycle. CONCLUSIONS: Mechanical interruption of urine flow by controlled inflation of a penile cuff during voiding does not inhibit detrusor contraction. This finding further validates our noninvasive technique of bladder pressure measurement and supports ongoing studies into its clinical usefulness.

Adolescent↗
PubMed2002

Noninvasive measurement of bladder pressure by controlled inflation of a penile cuff.

PURPOSE: A noninvasive test providing reliable objective quantification of bladder pressure during the voiding cycle would make an important contribution to the management of lower urinary tract symptoms. We developed a new noninvasive test to measure bladder pressure in males based on controlled inflation of a penile cuff during voiding. We compared the new technique with simultaneous invasive bladder pressure measurement. MATERIALS AND METHODS: We evaluated 7 volunteers and 32 patients. A conventional pressure flow study was performed first. The bladder was refilled, a penile cuff was fitted and after voiding commenced the cuff was inflated in steps of 10 cm. water every 0.75 seconds until urine flow was interrupted. The cuff was rapidly deflated, allowing flow to resume, and the cycle was repeated until the end of voiding. The flow rate was graphed against cuff pressure for each interruption cycle to determine the pressure at which flow was interrupted. This pressure was compared with simultaneous invasive isovolumetric bladder pressure. RESULTS: Invasive and noninvasive pressure measurements agreed well. Average cuff pressure at interruption of flow exceeded mean simultaneous isovolumetric bladder pressure plus or minus standard deviation by 14.5 +/- 14.0 cm. water. CONCLUSIONS: The new method provides noninvasive quantitative information on voiding bladder pressure in males. Further study is required to assess whether the technique can contribute to the management of lower urinary tract symptoms.

Adult↗
PubMed2001

A simple resolution procedure using the Staudinger reaction for the preparation of P-stereogenic phosphine oxides.

The resolution of a variety of (+/-)-P-stereogenic phosphines is achieved by exploiting the Staudinger reaction of a (+/-)-phosphine with enantiopure (1S,2R)-O-(tert-butyldimethylsilyl)isobornyl-10-sulfonyl azide. The resulting mixtures of diastereomeric phosphinimines are generally separable by fractional crystallization or flash chromatography. Subsequent acid-catalyzed hydrolysis provides the corresponding optically pure phosphine oxides in high yields.

Journal Article↗
PubMed2001

Transmission of penile cuff pressure to the penile urethra.

PURPOSE: We developed a noninvasive method to measure voiding bladder pressure by inflating a penile cuff to interrupt flow. We tested the underlying assumption that cuff pressure is transmitted to the penile urethra. MATERIALS AND METHODS: In 35 men we simultaneously recorded penile cuff and urethral pressure during 2 experimental protocols for 6 cuffs of various widths and manufactures. Initially a urethral pressure transducer was placed at the mid point of the cuff and urethral pressure was continuously recorded during cuff inflation. In experiment 2 cuff pressure was set at 120 cm. water and the urethral pressure profile was measured by withdrawing the urethral transducer through the cuff width. RESULTS: There was excellent agreement of cuff with urethral pressure over the range of 0 to 200 cm. water for cuffs 37 to 54 mm. wide. Narrower cuffs showed wider variation with less efficient transmission of cuff pressure to the urethral lumen. Similarly maximum pressure in the urethral pressure profile showed best agreement for cuffs 38 and 46 mm. wide. Wider cuffs produced higher and narrower cuffs produced lower transmitted pressure within the urethra. Cuff performance was also related to penile size. Results had good within-subject repeatability. CONCLUSIONS: We demonstrated that pressure transmission from cuff to urethra is optimal at a cuff width of 40 to 50 mm. and recommended this width for other investigations of noninvasive bladder pressure measurement.

Equipment Design↗
PubMed1999

Primary in situ extracorporeal shock wave lithotripsy in the management of ureteric calculi: results with a third-generation lithotripter.

OBJECTIVE: To review the results of primary in situ extracorporeal shock wave lithotripsy (ESWL) for the treatment of ureteric stones using a third-generation lithotripter, the Dornier MFL 5000 (Dornier Medizentechnic, Germany). PATIENTS AND METHODS: The study comprised a retrospective review of treatment outcome in 180 patients with 196 stones who were treated with primary in situ ESWL, assessing the success of this approach and establishing reasons for failure. RESULTS: At the 3-month follow-up, 88% of patients were stone-free; 21 patients failed ESWL and were treated by ureteroscopic stone extraction with no complications. Stone-free rates were 90% for upper ureteric, 89% for middle-third and 86% for lower-third calculi. Twenty-one patients required auxiliary procedures in the form of JJ stenting or nephrostomy. Failure of ESWL was associated with stone size (>1.3 cm) but not location or inadequate treatment. CONCLUSION: Where prompt access to ESWL is available, primary in situ ESWL remains an effective form of treatment for all ureteric calculi, although stone-free rates are lower for larger stones.

Female↗
PubMed1996

Primary choriocarcinoma of the urinary bladder: a case report.

We present a 37-year-old patient with primary choriocarcinoma arising in the urinary bladder, who received 5 months of intensive chemotherapy with a very good response. He died of a pulmonary embolus before his treatment could be completed. A post-mortem examination revealed extensive necrotic nodules in the lungs and brain. There was only one small focus of viable tumour in the brain. There was no residual tumour in the bladder, and no testicular tumours or scars fulfilling the criteria for a true extragonadal teratoma. It is likely that the origin of the bladder choriocarcinomas is from metaplasia/de-differentiation of a transitional cell carcinoma to the level of trophoblast. Lesser degrees of differentiation producing functional changes in the carcinoma cells with secretion of beta hCG without structural changes are much more common.

Adult↗
PubMed1995

Outcome of endoscopic bladder transection.

OBJECTIVE: To determine the clinical, symptomatic and objective urodynamic outcome of patients undergoing endoscopic bladder transection. PATIENTS AND METHODS: The study included 20 men and 30 women (mean age of 50 +/- 15 years, range 20-86) who underwent endoscopic bladder transection. Their underlying diagnoses were idiopathic detrusor instability (41), enuresis with instability (6), multiple sclerosis (2) and Parkinson's disease (1). A full-thickness endoscopic transection of the bladder was performed under general anaesthesia. Subjective assessment was performed using symptom scores (0-14 points) and a Visick grading system (group A-E). Objective assessment was carried out using urodynamic studies. The mean follow-up period was 6 years (57 +/- 22 months, range 6-85). RESULTS: The mean hospital stay was 8 +/- 3 days (range 3-22). No patients died after the operation. Postoperative complications included extra-peritoneal extravasation (2), recurrent urinary tract infection (5) and urethral stricture (1). Symptom scores before and after the operation were 9 +/- 2 (range 4-14) and 8 +/- 3 (range 1-14) points respectively. The overall outcome of the procedure was satisfactory in only eight (16%) patients. The mean duration of symptomatic relief was 17 weeks (range 3-53). There was no significant difference between urodynamic results before and after the operation. Bladder instability observed in all patients before operating was demonstrated in 93% of patients after the operation. CONCLUSION: The results of our study suggests that endoscopic bladder transection produces only a transient symptomatic relief in a few of those patients who have failed to respond to pharmacological manipulations. We do not feel that its continued role is justified.

Adult↗
PubMed1995

Tanagho bladder neck reconstruction in the treatment of adult incontinence.

We studied the effectiveness of tubularized bladder neck reconstruction in the treatment of 8 patients with complex incontinence using urodynamic and clinical methods. The patients had undergone Tanagho bladder neck reconstruction within the last 10 years. Three of the 8 patients were judged unsuitable for artificial sphincter implantation because of severe scarring, and loss of urethral and vaginal tissue. There were 7 women with epispadias or severe urethral damage as a consequence of obstetrical or gynecological procedures. Five patients underwent 7 concurrent procedures at the time of bladder neck reconstruction, including colposuspension (4), and closure of a fistula involving the bladder neck (1) and urethra (1) plus vaginal reconstruction (1). Of 8 patients 5 (63%) were completely continent and satisfied, 2 underwent ileal conduit diversion (1 because of incontinence and 1 refused clean intermittent self-catheterization), and 1 is incontinent and awaiting further treatment. The best results were noted in patients with a healthy bladder and periurethral tissues. Four of 5 patients (80%) deemed potentially suitable for artificial urinary sphincter insertion were satisfied compared to only 1 of 3 (33%) unsuitable for artificial urinary sphincter insertion. The Tanagho bladder neck reconstruction is a useful addition to the procedures that may be used by the reconstructive urological surgeon in the treatment of carefully selected patients with complex incontinence, particularly in women with epispadias who for various reasons may wish to avoid the long-term potential complications of an artificial urinary sphincter.

Adult↗
PubMed1995

A crowded ureter.

Explore the source record for details and available documents.

Foreign-Body Migration↗
PubMed1994

Bladder function in healthy volunteers: ambulatory monitoring and conventional urodynamic studies.

OBJECTIVE: To obtain data on conventional artificial filling cystometry and ambulatory monitoring in healthy asymptomatic control populations. SUBJECTS AND METHODS: Seventeen healthy volunteers were assessed by means of artificial filling cystometry (CMG), filling at rates of 50 ml/min (CMG 50) and 100 ml/min (CMG 100), and ambulatory monitoring (AM). RESULTS: Significant differences were found between AM and CMG with respect to: the pressure rise on filling (P < 0.02), voided volumes (P < 0.01) and maximum detrusor pressure on micturition (P < 0.01). Detrusor instability was found in 38% of volunteers on AM, in 17% on CMG 50, but in none on CMG 100. CONCLUSION: A range of baseline urodynamic values has been established which could provide the basis for future studies of ambulatory monitoring.

Adult↗
PubMed1992

Ambulatory monitoring of bladder pressure in low compliance neurogenic bladder dysfunction.

Upper tract dilatation is an important complication of neurogenic bladder dysfunction. Risk factors include incomplete bladder emptying with large residual volumes of urine and high tonic increases in bladder pressures during artificial filling. However, on natural bladder filling many of these patients do not have high tonic increases in detrusor pressures. We compared conventional urodynamic studies with ambulatory monitoring during natural bladder filling in 66 patients with low compliance neurogenic bladder dysfunction. There were marked differences in the tonic increase in bladder pressure during filling and in compliance during artificial bladder filling compared with ambulatory monitoring. Faster filling rates during artificial filling resulted in greater end filling pressures and lower compliance but the lowest increases in bladder pressure were found during ambulatory monitoring with natural bladder filling. During natural bladder filling significantly more patients had phasic changes in detrusor pressure; a high intensity of phasic activity during ambulatory monitoring correlated with high end filling pressures during artificial bladder filling. Upper tract dilatation was associated with large volumes of residual urine, high resting bladder pressures and low bladder compliance on filling at 100 ml. per minute. However, upper tract dilatation was most strongly associated with high intensity phasic pressure activity during natural bladder filling in combination with high residual urine volumes and high resting bladder pressures. On multivariate statistical analysis the intensity of phasic pressure activity during ambulatory monitoring was the best discriminator between patients with dilated and normal upper tracts. Our study has highlighted important differences in the results obtained by artificial filling cystometry and ambulatory monitoring during natural bladder filling. In particular, high increases in pressure did not occur during natural bladder filling, apparently being replaced by phasic activity. Within this group of patients who had the high risk factor of low bladder compliance measured during artificial bladder filling, a combination of greater residual urine volumes, greater resting pressures and greater phasic activity during natural bladder filling was found in patients with upper tract dilatation.

Adolescent↗
PubMed1991

The outcome of prostatectomy on chronic retention of urine.

A total of 68 men with bladder outflow obstruction and chronic retention (residual urine greater than 300 ml.) underwent investigation before and after prostatectomy with medium fill cystometry and natural fill long-term bladder pressure monitoring. Postoperatively, upper tract dilatation (present in 28 men preoperatively) resolved in all but 2 men and serum creatinine levels improved significantly. Irritative and obstructive symptom scores improved postoperatively (p less than 0.00006), although 17% of the men still had significant symptoms. Residual urine volumes decreased and flow rates improved (p less than 0.00006) but 32% of the men still had a residual urine of greater than 200 ml. Urodynamic parameters improved during medium fill cystometry and long-term monitoring. The main risk factors for upper tract dilatation are a pressure increase during bladder filling on conventional cystometry and the frequency of phasic detrusor activity during long-term monitoring, and they decreased postoperatively.

Aged↗
PubMed1991

Ambulatory monitoring and electronic measurement of urinary leakage in the diagnosis of detrusor instability and incontinence.

The ability of conventional artificial filling urodynamic studies (CMG) and ambulatory monitoring during natural bladder filling (AM) to detect phasic detrusor activity (detrusor instability) and incontinence was studied in 52 patients suspected on clinical grounds of having bladder dysfunction, but in whom a CMG had not provided an adequate explanation of their symptoms. Detrusor instability (DI) was found on AM in 31 patients who were not unstable on conventional CMG using the criteria of the International Continence Society: DI was diagnosed on filling in 20 patients and on provocation in a further 11. Incontinence was demonstrated by electronic nappy testing in 23 patients: 13 had urge incontinence due to DI, 7 had genuine stress incontinence alone and 3 had both genuine stress incontinence and detrusor instability. Thus DI was diagnosed significantly more frequently by AM than by CMG. Ambulatory monitoring was more sensitive in the diagnosis of instability and incontinence and it may prove to be a valuable aid in the diagnosis of bladder dysfunction not detected during conventional cystometry.

Adult↗
PubMed1990

Measurement of voiding pressures on ambulatory monitoring: comparison with conventional cystometry.

A series of 20 patients underwent conventional medium fill cystometry (CMG) and ambulatory monitoring during natural bladder filling (AM). The measurement of voiding pressures by the 2 techniques was compared. The maximum subtracted detrusor contraction pressure recorded during CMG (50 +/- 30 cm H2O) was significantly less than that recorded during AM (86 +/- 35 cm H2O). Voiding pressures during natural filling are greater than those observed during conventional urodynamic studies: this finding may have important implications in the definition of bladder outflow obstruction.

Adult↗
PubMed1989

Outcome of elective prostatectomy.

OBJECTIVES: To determine the symptomatic and urodynamic outcome of elective prostatectomy and to establish whether the outcome is influenced or can be predicted by preoperative urodynamic measurements. DESIGN: Prospective non-randomised study with follow up at a mean of 11 months after operation. Most men were assessed jointly by a urologist and a general practitioner. SETTING: Department of urology in a teaching hospital serving a large district population. PATIENTS: 253 Men listed for elective prostatectomy because of symptoms and low urinary flow rates (less than 15 ml/s) and excluding those already on a waiting list or with acute urinary retention, clinically apparent prostatic cancer, and neurological or cerebrovascular disease; 217 (86%) were followed up. INTERVENTION: Elective prostatectomy. MAIN OUTCOME MEASURE: Classification on the basis of relief of symptoms assessed by patients and urologist and general practitioner and of symptom scores obtained by questionnaire. RESULTS: Of the 217 men followed up, 171 (79%) had a satisfactory subjective review and 155 (72%) had a satisfactory review and also low symptom scores. An unsatisfactory outcome was associated with preoperative symptoms of urge incontinence, small prostatic size and resected weight, low voiding pressures, and low urethral resistance. Preoperative maximum urinary flow rates did not predict outcome. Men with poor outcome could be classified into two groups: those with irritative symptoms who were more likely before operation to have had urge incontinence and detrusor instability and men with symptoms of poor urinary flow who were more likely before operation to have had a small prostate, low voiding pressures, and low urethral resistance. In patients in the second group flow rates or voiding pressures improved little after operation. Men with stable detrusors and either low urethral resistance or low voiding pressures were less likely to do well after prostatectomy, but despite these associations preoperative urodynamic measurements were unable to predict outcome accurately. CONCLUSIONS: Prostatectomy was satisfactory in relieving symptoms and improving urodynamic measurements in most men, but even in those with classic symptoms and low urinary flow rates a substantial minority experienced little improvement afterwards and urodynamic measurements did not accurately predict outcome in individual patients.

Follow-Up Studies↗
PubMed1989

Ambulatory monitoring of bladder and detrusor pressure during natural filling.

We have developed a system to perform fully ambulatory monitoring studies of the bladder. Bladder and rectal pressures are recorded during natural filling of the bladder for up to 6 hours. This system has been evaluated in 19 studies performed on 15 patients. The mean duration of the studies was 3 hours 51 minutes (standard deviation +/- 1 hour 3 minutes) and the mean number of voids per patient was 3.8 +/- 2.2. Visual inspection of the recorded data showed that subtraction of the rectal trace from the bladder trace provided a useful detrusor trace when subjects were ambulant as well as resting. When ambulant, movement caused typical peak-to-peak pressure variability in the bladder and rectal traces of approximately 30 +/- 20 cm. water (mean and standard deviation of peak-to-peak pressure for typical ambulant 5-minute sections for each patient), which after subtraction was reduced on the detrusor trace to 10 +/- 5 cm. water. The equivalent figures when resting were 9 +/- 5 cm. water, subtracting to less than 5 cm. water for the detrusor. Further measurements also were calculated for the whole of each trace. The system provided good quality recordings and should prove useful in future evaluations of natural fill urodynamic studies.

Adult↗