The relationship between external anal and external urethral sphincter activity in continent women

The relationship between the external anal sphincter and the periurethral sphincter muscles is an unresolved issue. Recordings of the external anal sphincter (EAS) are commonly used to indicate the responses of the urethral sphincter during urodynamic evaluations and in biofeedback procedures for the treatment of urinary incontinence. This study examined the validity of using anal sphincter training to teach control of the external urethral sphincter. Subjects were 5 continent women, aged 37–51 years, who reported being free of all urologic symptoms. Using visual biofeedback of anal sphincter pressure, subjects were trained to voluntarily contract the sphincter to four amplitudes: 5, 10, 15, and 20 mmHg (6.8, 13.6, 20.4, and 27.2 cmH₂O). Then they were guided through a series of controlled anal sphincter contractions, while the response of the urethral sphincter was measured using surface electrodes embedded in a Foley catheter. At each of four bladder volumes, subjects performed 16 contractions (four contractions at each of the four amplitudes). The order of contractions was counterbalanced, using a Latin square design. The results show a strong, statistically significant, monotonic relationship between the magnitude of anal sphincter contraction (pressure) and the level of urethral sphincter electromyographic (EMG) activity. The results support the use of the external anal sphincter as an indicator of urethral sphincter activity for the purpose of conducting biofeedback in the treatment of urinary incontinence.     

Transvaginal ultrasound for the detection of urethral diverticula at urodynamic assessment

At the time of urodynamic assessment, 91 patients were examined by transvaginal echography. Two urethral diverticula were detected, one of which was only detected by ultrasound. Transvaginal echography clearly showed the size and anatomical relationship of the diverticulum to the bladder. We conclude that the procedure is a useful adjunct to routine testing for the detection of urethral diverticula.     

Rotational differences in urethral pressure in incontinent women

Urethral pressure profile measurements are made by means of microtransducers at four different positions in the urethra (anterior, posterior, left and right side). The maximum urethral closure pressure (MUCP) is always highest in the anterior position in stress as well as in urge incontinent women. The functional urethral length shows no differences in the four positions. In all positions the recorded pressures and urethral length are higher in the urge incontinent group than in the stress incontinent group. A decrease of MUCP with age is observed in both groups.     

Transvaginal ultrasound for the diagnosis of urethral diverticulum

PURPOSE: We reviewed our experience with urethral diverticula and transvaginal ultrasound to evaluate female patients with this condition. MATERIALS AND METHODS: All female patients who underwent transvaginal ultrasound during evaluation for urethral diverticulum at our institution between May 1995 and April 2002 were identified by searching a data base. We reviewed the diagnostic evaluation and compared diagnostic techniques with transvaginal ultrasound for diagnosing urethral diverticulum. RESULTS: Of the 25 patients with suspected urethral diverticulum who underwent transvaginal ultrasound as a diagnostic procedure 10 (40%) were diagnosed with urethral diverticulum, including 10 in whom it was confirmed by surgery or other diagnostic procedures. Transvaginal ultrasound was less expensive than the other diagnostic modalities and in no case did it miss a urethral diverticulum that was identified by another diagnostic technique. Urethral diverticulum was detected on 1 of 3 voiding cystourethrograms (33%) and this study missed the diagnosis in 1 case that was diagnosed by transvaginal ultrasound. Three cases of urethral diverticulum were noted on transvaginal ultrasound after they were missed by cystoscopy. Videourodynamics were unable to diagnose urethral diverticulum. CONCLUSIONS: Transvaginal ultrasound is effective for evaluating patients with suspected urethral diverticulum. It is less expensive and may identify diverticula missed by other diagnostic modalities.     

Pressure transmission ratio reproducibility in stress continent and stress incontinent women

Our objective was to determine the effect of cough strength on pressure transmission ratios and establish quantitative and qualitative intra-observer test-retest reproducibility of pressure transmission ratios calculated from dynamic urethral pressure profilometry. The study included 242 consecutive urodynamic evaluations on women without pelvic organ prolapse. Dynamic urethral pressure profiles were performed in duplicate with coughs of different intensities. The analysis included pressure transmission ratios from the proximal 3 urethral quartiles (Q1 through Q3) and the mean pressure transmission ratio calculated from these quartiles. The final diagnoses were stratified into genuine stress incontinence, 135 (56%), and stress continence, 107 (44%). Correlations were strong for pressure transmission ratios from the first versus the second dynamic urethral pressure profile (K = 0.712 for mean). While the variation in cough intensity between hard and soft coughs averaged 30 cm H₂O (P < 0.001), correlation's were equally strong between hard and soft cough pressure transmission ratios (K = 0.712 for mean). What mean pressure transmission ratios were stratified into below 90% and at least 90% categories, 83.5% of subjects had test-retest concordance (K = 0.671). Concordance rates were less for stress continent subjects (80.0%; K = 0.527) than for genuine stress incontinence subjects (86.4%; K = 0.679). Pressure transmission ratios appear to have reasonable quantitative and qualitative reproductibility which is unaffected by cough strength. The degree of individual variability limits the utility of pressure transmission ratios to diagnose genuine stress incontinence independent of other, equally variable clinical and urodynamic parameters, but this measure is sufficiently reproducible to be useful in characterizing stress sphincteric function in population studies. Neurourol. Urodynam. 16:161–166, 1997. © 1997 Wiley-Liss, Inc.     

Effect of narcotic anesthesia and skeletal muscle paralysis on passive and dynamic urethral function of stress continent and incontinent women

The aim of this study was to assess the importance of conscious skeletal muscle activity on the resting and stressed urethral sphincteric mechanism in stress continent and stress incontinent women. We evaluated the effects of loss of consciousness induced by a narcotic-based general anesthetic technique, with and without concurrent skeletal muscle paralysis, urethral sphincteric function. Nine premenopausal women who underwent vaginal hysterectomy without continence surgery had passive and dynamic urethral pressure profilometry performed within 24 hours before surgery, while asleep and totally paralyzed following endotracheal intubation before the start of surgery, while asleep and totally nonparalyzed at the end of surgery, and at the time of discharge from the hospital on the second or third postoperative day. Five subjects were stress incontinent and four had mild genuine stress incontinence but did not desire continence surgery with their hysterectomy. Measurements analyzed included urethral maximum closure pressure (MUCP) and functional length (FUL) from the passive profiles and bladder to urethra pressure transmission ratios (PTR) for each quarter of the urethra from the dynamic profiles. We found significant attenuation of urethral sphincteric function with stress due to muscle paralysis and loss of consciousness independent of muscle paralysis. Passive urethral function was more significantly depressed by paralysis than by loss of consciousness. These changes were statistically sifnificant only in stress continent subjects and not in the stress incontinent subjects, an observation that supports other evidence suggesting that there are important neuromuscular components in the pathogenesis of stress incontinence.     

Clinical evaluation of pelvic floor muscle function in continent and incontinent women

AIMS: The aim of the study was to investigate the reliability of a scoring system for the investigation of voluntary and reflex co-contractions of abdominal and pelvic floor muscles in lying, sitting, and standing positions in continent and incontinent women. METHODS: A visual inspection and digital (strength, tone, speed, and endurance) palpation scale was developed to measure the coordination of the lower abdominal and pelvic floor muscles. Inter-observer reliability of the scales was investigated in 40 continent and 40 incontinent women. Differences between the continent and incontinent group were analysed. RESULTS: Inter-observer reliability for the visual inspection scale showed kappa values between 0.91 and 1.00, for tone percentage of agreement ranged from 95 to 100% (superficial) and 95 to 98% (deep muscle). Weighted Kappa (K(w)) varied from 0.77 to 0.95 for strength and 0.75 to 0.98 for the inward movement of superficial and deep pelvic floor muscles. K(w) for coordination between the superficial and deep part of the pelvic floor muscles groups was from 0.87 to 0.88 and 0.97 to 1.00 for endurance and global speed of the pelvic floor contraction. The continent women exhibited significantly better coordination between the pelvic floor and lower abdominal muscles during coughing in all three positions. Also the superficial part of the inward movement, the feeling and the coordination of the pelvic floor muscles were significantly better in the continent group. CONCLUSIONS: Visual inspection and digital tests are easy and reliable methods by which insight can be gained into the multi-muscular activity and coordination of the pelvic floor and lower abdominal muscles in continent and incontinent women.     

The urethral pressure profiles in continent and stress-incontinent women

Simultaneous urethrocystometry, including recording of the urethral pressure profile, was performed in 127 women aged 30 to 69 years; 42 of the women were free from urologic disorders and 85 had stress incontinence of urine. Both groups were subgrouped according to age. The results in the continent and the incontinent women were analyzed separately, in order to disclose any age-related changes. The data within each decade of age were also comparatively analyzed. In the bladder pressure at rest no age-related changes were found, and the readings were similar in the continent and the incontinent women. The maximum urethral pressure fell significantly with rising age in both groups and was significantly reduced in stress incontinence. The urethral closure pressure showed variations similar to those in the maximum urethral pressure. No lower limit of urethral closure pressure that definitely predisposed to stress incontinence could be established. The functional length of the urethra diminished significantly with rising age in the continent, but not in the incontinent women. The absolute length of the urethra did not show such diminution. Both the functional and the absolute urethral length were significantly less in the incontinent than in the continent women in the age groups between 30 and 49 years.     

Urethral pressure response patterns induced by squeeze in continent and incontinent women

Our aim was to compare the urethral pressure response pattern to pelvic floor muscle contractions in 20–27 years old, nulliparous continent women (n = 31) to that of continent (n = 28) and formerly untreated incontinent (n = 59) (53–63 years old) women. These women underwent urethral pressure measurements during rest and repeated pelvic muscle contractions. The response to the contractions was graded 0–4. The young continent women showed a mean urethral pressure response of 2.8, the middle-aged continent women 2.2 (NS vs young continent), and the incontinent women 1.5 (p < 0.05 vs middle-aged continent, p < 0.001 vs young continent). Urethral pressures during rest were significantly higher in the younger women than in both groups of middle-aged women. The decreased ability to increase urethral pressure on demand seen in middle-aged incontinent women compared to continent women of the same age as well as young women seems to be a consequence of a neuromuscular disorder rather than of age.     

The effect of catheter diameter on the urethral cough pressure profile of continent and incontinent patients

The importance of catheter diameter in causing inaccurate urethral pressure profile recordings was assessed with the aid of a special, dual diameter catheter. Cough pressure profiles obtained in premenopausal and postmenopausal incontinent patients were compared with control groups. The urethral functional length (FL) and pressure transmission ratio (PTR) did not change. The maximal urethral closing pressure (MUCP) decreased with the smaller catheter only in incontinent patients. Similarly, a decreased urethral surface at rest (USR) was observed for incontinent groups. Continent patients showed no modification of MUCP or USR with change in catheter diameter. The occlusive effect of the catheter was high (21 cmH₂O) in incontinent patients and less in continent patients (5 cmH₂O). The part played by the occlusive effect of the catheter may therefore be evaluated and considered an element explaining artificially high MUCP that do not reflect clinical reality in certain patients. This occurs most often in incontinent patients due to curvature of the catheter during coughing.     

Neurophysiologic effect of vaginal cone application in continent and urinary stress incontinent women

Simultaneous electromyographic (EMG) recordings with intramuscular wire electrodes from the left and right pubococcygeal muscles were performed to elucidate the neurophysiological effect of vaginal cones on the pelvic floor muscles. Ten continent nulliparous women (aged 22–32 years) and 20 stress urinary incontinent parous women (aged 27–60 years, average 2–4 deliveries) were examined before, during holding and after removal of the cone. All the continent nulliparous women could retain the cone in the vagina (mean weight 83.5 g (range 70–85 g). In the incontinent parous group 7 women could not hold any cone, 9 women could hold the 45 g cone, 1 the 32.5 g cone and 3 women the 57.5g cone. There was a significant voluntary holding time difference between continent nulliparous and incontinent parous women. The study reveals that vaginal cones may induce both strengthening of muscles as well as a learning effect leading towards a better coordinated muscle activation.Editorial Comment. This paper gives more clarification as to the (good) effect of vaginal cones. Even though Plevnik and co-authors suspected some kind of reflex activity in 1985, this study demonstrates nicely the electromyographic effects, including intermittent activation as well as possible recruitment of motor units even in previously unilateral inhibited motor units. A prerequisite of this treatment is good compliance and the ability to retain the cones, which was impossible in 7 out of 20 women.     

Pelvic floor muscle strength and thickness in continent and incontinent nulliparous pregnant women

The aim of the study was to measure pelvic floor muscle function in continent and incontinent nulliparous pregnant women. The study group consisted of 103 nulliparous pregnant women at 20 weeks of pregnancy. Women reporting urinary incontinence once per week or more during the previous month were classified as incontinent. Function was measured by vaginal squeeze pressure (muscle strength) and increment in thickness of the superficial pelvic floor muscles (urogenital diaphragm) assessed by perineal ultrasound. Seventy-one women were classified as continent and 32 women as incontinent. Continent women had statistically significantly higher maximal vaginal squeeze pressure and increment in muscle thickness when compared with incontinent women. There was a strong correlation between measurements of vaginal squeeze pressure and perineal ultrasound measurements of increment in muscle thickness. This study demonstrates statistically significant differences in pelvic floor muscle function measured by strength and thickness in continent compared with incontinent nulliparous pregnant women. Editorial Comment: This study evaluated pelvic floor muscle function in 103 nulliparous continent and incontinent women at 18–20 weeks gestation. Pelvic floor muscle strength was assessed by measuring vaginal squeeze pressure, and thickness of the urogenital diaphragm during both relaxation and contraction was measured using perineal ultrasound. The authors found a statistically significant higher vaginal squeeze pressure and higher mean increment in muscle thickness in the continent compared with incontinent group as well as a strong correlation between pelvic floor muscle strength and increment in thickness. Although describing several benefits of ultrasonography in assessing pelvic floor muscles, the authors did acknowledge the difficulty in identifying and measuring these muscles, and the learning curve involved with perineal ultrasound. Another limitation was the subjective classification of continence status based on self-reported symptoms. The implication of low pelvic floor muscle strength and thickness as risk factors for the development of urinary incontinence is beyond the scope of this study.     

Pubococcygeal activity on perineal ultrasound in incontinent women

Introduction and hypothesis  

The aim of this study was to investigate the applicability and reproducibility of perineal ultrasound (US) in the evaluation of the pubococcygeal muscle (PCM) activity in urinary incontinent women.     

Comparison of transperineal and transabdominal ultrasound in the assessment of voluntary pelvic floor muscle contractions and functional manoeuvres in continent and incontinent women

Transperineal (TP) and transabdominal (TA) ultrasounds were used to assess bladder neck (TP) and bladder base (TA) movement during voluntary pelvic floor muscle (PFM) contraction and functional tasks. A sonographer assessed 60 asymptomatic (30 nulliparous, 30 parous) and 60 incontinent (30 stress, 30 urge) women with a mean age of 43 (SD = 7) years, BMI of 24 (SD = 4) kg m² and a median parity of 2 (range, 0–5), using both ultrasound methods. The mean of three measurements for bladder neck and bladder base (sagittal view) movement for each task was assessed for differences between the groups. There were no differences in bladder neck (p = 0.096) or bladder base (p = 0.112) movement between the four groups during voluntary PFM contraction but significant differences in bladder neck (p < 0.004) and a trend towards differences in bladder base (p = 0.068) movement during Valsalva and abdominal curl manoeuvre. During PFM contraction, there was a strong trend for the continent women to have greater bladder neck elevation (p = 0.051), but no difference in bladder base movement (p = 0.300), when compared to the incontinent women. The incontinent women demonstrated increased bladder neck descent during Valsalva and abdominal curl (p < 0.001) and bladder base descent during Valsalva (p = 0.021). The differences between the groups were more marked during functional activities, suggesting that comprehensive assessment of the PFM should include functional activities as well as voluntary PFM contractions. TP ultrasound was more reliable and takes measures from a bony landmark when compared to TA ultrasound, which lacks a reference point for measurements. TA ultrasound is less suitable for PFM measures during functional manoeuvres and comparisons between subjects. Few subjects were overweight so the results may not be valid in an obese population.