N. Schmidt

University Hospital of Lausanne, Lausanne, Vaud, Switzerland

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Publications (9)15.09 Total impact

  • S Meyer · P De Grandi · N Schmidt · W Sanzeni · J P Spinosa
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    ABSTRACT: This study evaluates the usefulness of the urethral pressure profile (UPP) parameters in assessing the severity of genuine stress incontinence (GSI). Functional length (FL), maximum urethral closure pressure (MUCP), pressure transmission ratio (PTR), residual area at stress (RAS), number of patients with incontinent spikes (IS), and distribution of IS on UPP were determined in supine and standing position for 54 patients (group 1) with a 1-hour pad test < 2 g and compared with the values of 63 patients (group 2) with a 1-hour pad test > 2 g. The results were similar: FL (supine: 24 mm +/- 6/26 mm +/- 7 [P:0.2]; standing: 26 mm +/- 8/24 mm +/- 11 [P:0.5]); MUCP (supine: 51 cm H2O +/- 23/47 cm H2O +/- 20 [P:0.3]; standing: 45 cm H2O +/- 21/38 cm H2O +/- 18 [P:0.1]); and PTR (supine: 83% +/- 27/84% +/- 31 [P:0.9]; standing: 81% +/- 25 and 88% +/- 27 [P:0.3]). But the RAS was lower (supine: 502 mm2 +/- 497/246 mm2 +/- 268 [P < 0.009]; standing: 500 mm2 +/- 534/271 mm2 +/- 306 [P < 0.05]) in group 2. If the percentage of patients with IS was higher (supine: 57/93% [P < 0.001]; standing: 54/84% [P < 0.01]) in group 2, the distribution of IS over the entire FL demonstrated no differences between group 1 and 2. In conclusion, except for the RAS, standard UPP parameters cannot be considered determinant in assessing the severity of GSI.
    No preview · Article · Jan 1994 · Neurourology and Urodynamics
  • S. Meyer · P. De Grandi · N. Schmidt · W. Sanzeni
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    ABSTRACT: In order to evaluate the obstructive effects of microtip transducer catheters on flowmetry parameters, 156 patients had a spontaneous uroflowmetry (SU) followed by an instrumented uroflowmetry (IU), with intravesical pressure recording for comparison of maximum flow rate (Qmax), corrected maximum flow rate for volume voided (Qmax.corr.), time to maximum flow rate (TQmax), and flow curve patterns. With SU and IU, Qmax values were 26±11 ml/s compared with 21±11 ml/s (Pmax.corr. as 29±10 m/s compared with 21±11 ml/s (Pmax values were 11±9 s compared with 30±52 s (Pmax (2O±20) than with a higher TQmax (17 cmH2O±16) (Pmax and Qmax.corr. and an increase in TQmax values, due to a lowered VOP in many patients, but little difference in curve pattern interpretation.
    No preview · Article · Oct 1993 · International Urogynecology Journal
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    ABSTRACT: Birth trauma is the most important etiological factor in the genesis of stress urinary incontinence in women (SUI). There is a high incidence of SUI during pregnancy, and after delivery SUI persists in a small percentage of women (2-3%). Almost all studies on perineal muscle function reveal decreasing intravaginal pressures in the days after delivery which rarely return to predelivery levels. A few urodynamics studies have demonstrated reduced urethral closure pressures and functional length after vaginal delivery, but the importance of such findings in the genesis of SUI is controversial. Better consensus has been found when pelvic floor neurophysiology was carried out: there is electromyographic evidence of a denervation-reinnervation pattern in the striated urethral sphincter muscle and occasionally prolonged pudendal conduction times when the pudendal nerves are directly stimulated. Histomorphologic studies of the pelvic floor have demonstrated that, in some women, abnormal collagen types are responsible for vaginal prolapse and accompanying SUI. Finally, the great importance of perineal reeducation by electromyostimulation and biofeedback in patients with traumatic pelvic floor pathology may be emphasized, but the importance of its role in the prevention of late SUI development remains to be established by more prospective studies.
    No preview · Article · Feb 1993 · Gynäkologisch-geburtshilfliche Rundschau
  • S. Meyer · P. De Grandi · N. Schmidt
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    ABSTRACT: The effect of babies >3500 g primimultiparity, previous forceps deliveries, obesity and stress urinary incontinence on urethrovesical junction mobility (UVJ) was determined by the Q-tip test in 440 women divided into four groups according to age. The urethral axis under stress (UAS) for these different categories of patient compared to corresponding nulliparous patients (4921) demonstrates an increasing statistically significant difference in UVJ mobility in primiparas (5621), multiparas (5819), patients with previous forceps delivery (5921) and with deliveries of babies >3500 g (6117). Surprisingly, obesity does not affect UVJ mobility. Except for postmenopausal women, assessment of UAS in patients with GSI by history demonstrates a 5 higher UVJ mobility compared to continent patients (a 10 higher UVJ mobility was found in a fifth group of clinically proven GSI patients). When considering UAS distribution in the four groups, only 6%–33% of nulliparas have a normal UAS of 60, demonstrating perhaps an increased risk of future GSI.
    No preview · Article · Jan 1993 · International Urogynecology Journal
  • S Meyer · T Dhenin · N Schmidt · P De Grandi
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    ABSTRACT: A group of 36 patients (18 premenopausal and 18 postmenopausal), all suffering from genuine stress urinary incontinence, underwent conservative treatment with 6 sessions of intravaginal electromyostimulation followed by 6 sessions of biofeedback; 89% of patients reported an improvement, 5.5% considered themselves cured and 5.5% reported no change. Intravaginal pressure measured before and after therapy increased by an average of 11 cm H2O in premenopausal patients and 17 cm H2O in the postmenopausal group. Intravaginal pressure increased in all patients and, according to maximal urethral closure pressure, this increasing intravaginal pressure was observed even in patients with low pressure urethras. The urodynamic factors studied were functional length, maximum urethral closing pressure and pressure transmission, together with urethral surface at rest and during stress, and residual surface. No significant changes were noted before and after treatment. The excellent subjective results contrast with the absence of improvement in these values.
    No preview · Article · Jul 1992 · British Journal of Urology
  • S. Meyer · P. de Grandi · N. Schmidt · O. Reymond
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    ABSTRACT: 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.
    No preview · Article · Feb 1992 · International Urogynecology Journal
  • S Meyer · P DeGrandi · N Schmidt
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    ABSTRACT: The correlation between clinical and tonometric incontinence is frequently poor, with urethral profile results that do not correspond to clinical reality. Among potential causal factors, we have attempted to determine the importance of the absorption of kinetic energy from the mass of urine driven against the urethral captor (the hydraulic ram effect). Twenty patients (average age 50 +/- 10 years, para 2) suffering from genuine stress urinary incontinence, underwent urodynamic investigation with a constant air-flow pneumatic catheter equipped with two captors separated by an inflatable cuff located just above the urethral captor to block the inrush of urine into the urethra. After cystometric examination had excluded an unstable bladder, two urethral profiles were registered successively, first with cuff deflated, and then with cuff inflated. The values for urethral functional length (FL) and transmission factor (TF) show no significant changes. The values for the maximal urethral closing pressure (MUCP) were significantly lower in the second profile (cuff inflated) in 18 of 20 cases (average decrease 7 cm H2O), which corresponds to 14 percent of the average MUCP measured during the first profile (cuff deflated). The depression quotient increased from an average 0.80 to 1.05 from first to second profile. This study allows quantification of the urethral "hydraulic ram effect" which modifies determination of the MUCP during registration of urinary stress profile.
    No preview · Article · Sep 1991 · Urology
  • S MEYER · P DEGRANDI · N SCHMIDT
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    ABSTRACT: The correlation between clinical and tonometric incontinence is frequently poor, with urethral profile results that do not correspond to clinical reality. Among potential causal factors, we have attempted to determine the importance of the absorption of kinetic energy from the mass of urine driven against the urethral captor (the hydraulic ram effect). Twenty patients (average age 50 +/- 10 years, para 2) suffering from genuine stress urinary incontinence, underwent urodynamic investigation with a constant air-flow pneumatic catheter equipped with two captors separated by an inflatable cuff located just above the urethral captor to block the inrush of urine into the urethra. After cystometric examination had excluded an unstable bladder, two urethral profiles were registered successively, first with cuff deflated, and then with cuff inflated. The values for urethral functional length (FL) and transmission factor (TF) show no significant changes. The values for the maximal urethral closing pressure (MUCP) were significantly lower in the second profile (cuff inflated) in 18 of 20 cases (average decrease 7 cm H2O), which corresponds to 14 percent of the average MUCP measured during the first profile (cuff deflated). The depression quotient increased from an average 0.80 to 1.05 from first to second profile. This study allows quantification of the urethral "hydraulic ram effect" which modifies determination of the MUCP during registration of urinary stress profile.
    No preview · Article · Aug 1991 · Urology
  • S. Meyer · P. de Grandi · N. Schmidt
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    ABSTRACT: In this study 272 patients with genuine stress urinary incontinence (GSUI) were initially considered. Of these, 247 were divided into three groups based on: positive history for GSUI (group 1); positive history and clinical examination for GSUI (group 2); and positive history, clinical examination, and cough urethral pressure profile for GSUI (group 3). When compared with a group of 30 normal women (control group) the values for the urethral functional length (FL) and the maximum urethral closure pressure (MCUP) decreased progressively from group 1 to group 3. The pressure transmission ratio (PTR) was signficantly lower only in group 3. Tonometric values calculated for a group of 25 patients with GSUI recurring afterprevious surgical correction (group 4) were found to be comparable with group 3. These patients with recurrent GSUI had a FL decreased to 70% and a MCUP decreased to 48% of the normal values. The PTR was maintained at a normal value of 97% in patients with degree I recurrence, but was decreased to 68% in patients with degree II–III recurrence having the most severe impairment of the periurethral environment.
    No preview · Article · Dec 1990 · International Urogynecology Journal