The objective of this study was to investigate the stability in terms of volume changes and local tissue reactions of dextranomer (Dx)/hyaluronic acid (HA) and collagen implants. A total of 57 rats were included in this study: the control group (nine rats), collagen-injected group (24 rats), and Dx/HA copolymer-injected group (24 rats). Under anesthesia, 0.35 ml of bulking agents was injected subcutaneously in the abdominal area. At 1, 6, and12 months, eight animals of the two implant groups and three animals of the control group were killed. The area of the injected material and surrounding tissue were carefully resected for histopathological examination. Mean volume changes in the Dx/HA copolymer group were 0.56 +/- 0.12, 0.43 +/- 0.08, and 0.28 +/- 0.02 ml at 1, 6, and 12 months, respectively. Mean volume changes in the collagen group were 0.25 +/- 0.03, 0.21 +/- 0.08, and 0.21 +/- 0.01 at 1, 6, and 12 months, respectively. The degree of tissue reaction and fibrosis are more pronounced in the Dx/HA copolymer group at each measurement period after injection.

To evaluate the potential of calcium hydroxylapatite particles as a bulking material for the treatment of stress incontinence.

Ten women (mean age 68 years, range 60 to 82) with stress incontinence associated with intrinsic sphincter deficiency and limited hypermobility were treated with one (3 patients) or two (7 patients) injections of calcium hydroxylapatite particles and were followed up for 1 year subsequent to the last injection.

The mean total volume injected was 3.9 mL. No significant safety issues were identified with regard to local pain, infection, induration, or obstruction. Seven women reported substantial improvement using many fewer pads or none at all (3 patients) at 1 year, 2 women reported fewer pads, and 1 patient reported no change. The daily mean pad use declined from 2.59 to 1.64 and the mean 24-hour pad weight declined by more than 90% (104.9 versus 1.5 g). The mean Valsalva leak point pressure (VLPP) increased from 39 to 46 cm H(2)O at 12 months, with 2 patients dry on testing.

The results of this small initial study suggest that calcium hydroxylapatite particles have potential as a bulking agent for the treatment of stress incontinence.

The treatment of faecal incontinence secondary to internal anal sphincter dysfunction is unsatisfactory. The aim of the study was to evaluate the efficacy of anal glutaraldehyde cross-linked (GAX) collagen injections in patients with a surgically incorrectable disorder.

Seventeen patients were studied: nine had idiopathic faecal incontinence, three had incontinence following haemorrhoidectomy, two following internal sphincterotomy, two following an internal sphincter defect from obstetric injury and one following treatment for fistula in ano. All patients were refractory to conservative treatment and were unsuitable for surgical repair. All had anorectal physiology and endoanal ultrasonography before and after GAX collagen injections.

All patients tolerated the injection without side-effects. All patients had an intact external anal sphincter. Following injection, 11 patients showed marked symptomatic improvement. One patient reported symptomatic improvement but remained in clinical grade 3, and two reported minimal improvement. There was no improvement in three patients, but one of these had a repeat injection and showed significant improvement subsequently.

Injection of GAX collagen in the anal canal is a simple and well tolerated method of treating faecal incontinence due to internal sphincter dysfunction. Early results suggest it provides an easy and reliable alternative to the currently available methods that are often unsuccessful and at best unpredictable.

To assess the role of urodynamics in the prediction and assessment of outcome and analysis of the mechanism of cure for stress incontinence using periurethral collagen as our treatment model.

Prospective longitudinal study.

A teaching hospital tertiary referral centre.

Sixty women with genuine stress incontinence.

The objective cure rate was 54% (n = 54) at 12 months. Subtracted cystometry, urethral electrical conductivity and bladder neck excursion measurements did not predict cure. A low pre-injection maximum urethral closure pressure adversely affects outcome (31 cmH2O (success) vs 19 cmH2O (failure), P = 0.004); all women with a maximum urethral closure pressure > 39 cmH2O were rendered dry. Urethral pressure profilometry can analyse mechanism of cure. Total profile length, stress maximum urethral closure pressure, stress functional urethral length and pressure transmission ratio in the first quarter of urethral length were increased in successful cases (P < 0.05), and rest maximum urethral and maximum urethral closure pressures, area under rest profile and pressure transmission ratio in the second quarter of urethral length were increased in failed cases (P < 0.02).

In successful cases the increased area and pressure transmission ratio in the first quarter of the functional urethral length suggest that collagen placement occurs at the bladder neck or proximal urethra. Cure appears to be due to prevention of bladder neck opening during stress and not obstruction. In addition the cephalad elongation of the urethra caused by collagen probably accounts for the increased abdominal pressure transmission in the first quarter of the urethra. In failures, there is an increased length and increased area to peak pressure suggesting collagen is deposited more distally. This study confirms the role of certain urethral pressure profilometry variables in the prediction and analysis of mechanism of cure.

The questions of patient selection parameters and durability of response in the use of collagen injections for genuine stress incontinence are addressed. A total of 181 women with a mean age of 64 years (range 26-94) underwent collagen injections for urethral incompetence. Treatment outcome was determined by a change in individual incontinence grades before and after injection. Of the 181 women 42 (23%) are cured, 94 (52%) are improved and 45 (25%) failed. Follow-up in the successful patients, either cured or improved, was a mean of 21 months (range 4-69) after their last collagen injection. No difference in outcome was seen in relation to patient age or pretreatment grade of incontinence. Of the 30 patients with bladder instability, 18 (60%) had a favorable outcome. No significant difference in outcome was seen in patients with or without hypermobility (P = 0.2889). Patients with type III incontinence required the largest amount of collagen for a successful outcome. The persistence of continence in 78 patients who were cured for at least 2 months were plotted on a Kaplan-Meier survival curve. The probability of remaining dry without additional collagen was 72% at 1 year, 57% at 2 years and 45% at 3 years. It was concluded that, collagen injection into the urethra is a safe and well-tolerated procedure. Pretreatment bladder instability may be an adverse factor. Patients with or without hypermobility had equal benefit. Long-term durability was seen. If deterioration occurred repeat collagen injections restored success. The current literature is reviewed and the use of collagen relative to other treatments is discussed.

To assess the short- and medium-term efficacy of periurethral collagen injection in women with urethral sphincter incompetence and to determine if urodynamic variables can elucidate the mechanism of action.

Sixty women (mean age 64 years, range 20-90) with genuine stress incontinence received periurethral collagen injections under local anaesthesia; 55 had undergone previous continence surgery. A total of three injection sessions were allowed. Subjective and urodynamic assessments were obtained at 1, 3, 6, 12 and 24 months after injection to evaluate success and long-term effects of collagen.

Subjective success rates were 86% at 3 months, 77% at 12 months and 68% at 24 months. Objective cure rates were 61% at 3 months, 54% at 12 months and 48% at 24 months. Low urethral pressures and decreased bladder neck mobility did not affect the outcome. Collagen injections significantly increased stress maximum urethral closure pressures and functional urethral length; increase in the latter and clinical assessment of bulking at the time of injection appeared to predict medium-term success. There were some minor early complications and none in the medium-term.

Periurethral collagen injections continued to be effective at the 2-year follow-up, although there was a time-dependent decline. In comparison with more complicated procedures used in patients with previous failed continence surgery, periurethral collagen injection is a simple, acceptable, day case procedure which improves the quality of life in physically fit or frail patients, with few complications.

Urinary incontinence is a common problem that affects millions of elderly men and women and their caregivers. Evaluation of incontinence is easy and inexpensive and does not require hospitalization. A basic evaluation consists of history taking (including a review of drug use), physical examination, and appropriate laboratory testing. Urodynamic evaluation may also be necessary. Treatment may consist of behavior modification techniques (eg, Kegel exercises, biofeedback, bladder retraining), use of a mechanical device or pharmacologic agent, or surgery. Should medical and surgical methods fail, alternatives are available to ensure patients' well-being and comfort.