Relationship between intra-abdominal pressure and vaginal wall movements during Valsalva in women with and without pelvic organ prolapse: technique development and early observations.

OBJECTIVES: To develop and test a method for measuring the relationship between the rise in intra-abdominal pressure and sagittal plane movements of the anterior and posterior vaginal walls during Valsalva in a pilot sample of women with and without prolapse. METHODS: Mid-sagittal MRI images were obtained during Valsalva while changes in intra-abdominal pressure were measured via a bladder catheter in 5 women with cystocele, 5 women with rectocele, and 5 controls. The regional compliance of the anterior and posterior vagina wall support systems were estimated from the ratio of displacement (mm) of equidistant points along the anterior and posterior vaginal walls to intra-abdominal pressure rise (mmHg). RESULTS: The compliance of both anterior and posterior vaginal wall support systems varied along different regions of vaginal wall for all three groups, with the highest compliance found near the vaginal apex and the lowest near the introitus. Women with cystocele had more compliant anterior and posterior vaginal wall support systems than women with rectocele. The movement direction differs between cystocele and rectocele. In cystocele, the anterior vaginal wall moves mostly toward the vaginal orifice in the upper vagina, but in a ventral direction in the lower vagina. In rectocele, the direction of the posterior vaginal wall movement is generally toward the vaginal orifice. CONCLUSIONS: Movement of the vaginal wall and compliance of its support is quantifiable and was found to vary along the length of the vagina. Compliance was greatest in the upper vagina of all groups. Women with cystocele demonstrated the most compliant vaginal wall support.

On pelvic reference lines and the MR evaluation of genital prolapse: a proposal for standardization using the Pelvic Inclination Correction System.

Five midsagittal pelvic reference lines have been employed to quantify prolapse using MRI. However, the lack of standardization makes study results difficult to compare. Using MRI scans from 149 women, we demonstrate how use of existing reference lines can systematically affect measurements in three distinct ways: in oblique line systems, distances measured to the reference line vary with antero-posterior location; soft issue-based reference lines can underestimate organ movement relative to the pelvic bones; and systems defined relative to the MR scanner are affected by intra- and interindividual differences in the pelvic inclination angle at rest and strain. Thus, we propose a standardized approach called the Pelvic Inclination Correction System (PICS). Based on bony structures and the body axis, the PICS system corrects for variation in pelvic inclination, at rest of straining, and allows for the standardized measurement of organ displacement in the direction of prolapse.

Changes in self-assessment of continence status between telephone survey and subsequent clinical visit.

AIMS: To explore variance in reporting continence information obtained by telephone survey with face-to-face clinician interview in a clinical setting. METHODS: As part of a cross-sectional, epidemiologic study of incontinence prevalence among Black and White women aged 35-64 years, randomly selected households were contacted from geographic areas of known racial composition. Of 2,814 women who completed a 20-min, 137-item telephone interview, 1,702 were invited for future components of the study. A subset of these women was recruited for a clinical evaluation that was conducted within a mean of 82 days (SD 38 days) following the interviews. Prior to urodynamics testing, a clinician interview was conducted inquiring about continence status. The criterion for incontinence for both the telephone interview and the clinician interview was constant: 12 or more episodes of incontinence per year. Women whose subjective reports of continence information differed between telephone and clinician interviews were designated as "switchers." RESULTS: Of the 394 women (222 Black and 172 White) who completed the clinical portion, 24.6% (n = 97) were switchers. Switchers were four times more likely to change from continent to incontinent (80.4%, N = 78) than from incontinent to continent (19.4%, N = 19; P = 0.000) and nearly three times more likely to be Black (69%, N = 67) than White (31%, N = 30; P = 0.001). Telephone qualitative interviews were completed with 72 of the switchers. The primary reason for switching was changes in women's life circumstances such as variation in seasons, activities of daily living, and health status followed by increased awareness of leakage secondary to the phone interview. CONCLUSION: One-time subjective telephone interviews assessing incontinence symptoms may underestimate the prevalence of incontinence especially among Black women.

Test-retest reliability of an instrumented speculum for measuring vaginal closure force.

AIMS: The study aimed to: a) determine reliability of an instrumented speculum designed for measuring intravaginal closure pressure, and b) compare findings with a comparable device reported in the literature. The goal of these new devices is to reduce subjectivity, improve precision, and acknowledge reliability issues in quantifying levator ani closure force acting on the vagina. METHODS: The instrumented speculum consisted of two parallel aluminum bills, similar in size to a Peterson speculum. Strain gages located near the root of each bill measure the magnitude of force exerted in the distal vagina. A contraction of the "U-shaped" levator ani muscle closes the levator hiatus with resultant reaction force measured by the speculum in the mid-sagittal plane. We tested the device in twelve nulliparous women making repeated measures within and across 3 different visit days. All measures were made by the same investigator. RESULTS: Same day measures were repeatable within +/-3.8 N by the third visit, with lesser repeatability on the 1st and 2nd visit days. Across days, repeatability was improved by Visits 2 and 3 with a coefficient of repeatability between those days of +/-5.5 N. Better repeatability was obtained using averaged scores rather than 'best effort' ; but average scores can underestimate best effort. CONCLUSION: Reasonable within-visit repeatability was found. Across-visit repeatability is consistent with the known difficulty that women have in maximally isolating and activating their levator ani muscles. The results corroborate the repeatability results of Dumoulin et al. [2004] using a similar type of dynamometer.

Revisiting reliability of quantified perineal ultrasound: Bland and Altman analysis of a new protocol for the rectangular coordinate method.

AIMS: This study tested the reliability of a new protocol for the rectangular coordinate method of quantifying perineal ultrasound. METHODS: Representative scans of healthy primiparous females were quantified by positioning a pubic bone template, drawn onto an acetate sheet containing x-y axes, over scans, by aligning the x-axis with the pubic bone central axis. Values for x (D(x)) and y (D(y)) located the urethrovesical junction (UVJ) at Rest, and at maximal Valsalva and Kegel. Range of motion (V-K) was calculated. Bland and Altman analysis, correlations, and t-tests determined intra- and inter-rater reliability, and variance due to designation of the pubic bone central axis (template control). RESULTS: Correlations averaged 0.72, 0.70, and 0.92 for intra-rater, inter-rater, and template control experiments. D(x) Rest, D(x) Kegel, and V-K were reliable in all experiments. First and second measures for inter-rater D(y) Rest and D(y) Kegel, and template control D(y) Valsalva were significantly different. Bland and Altman analysis showed D(y) Rest, D(y) Kegel, and D(x) and D(y) Valsalva for both reliability experiments to have limits of agreement (LOA's) large enough to explain >or=50% of the actual value ranges. Template control LOA's explained

Measurement of the pubic portion of the levator ani muscle in women with unilateral defects in 3-D models from MR images.

OBJECTIVE: Develop a method to quantify the cross-sectional area of the pubic portion of the levator ani muscle, validate the method in women with unilateral muscle defects, and report preliminary findings in those women. METHOD: Multi-planar proton density magnetic resonance images of 12 women with a unilateral defect in the pubic portion of their levator ani were selected from a larger study of levator ani muscle anatomy in women with and without genital prolapse. Three-dimensional bilateral models of the levator ani were reconstructed (using 3-D Slicer, version 2.1b1) and divided into iliococcygeal and pubic portions. Muscle cross-sectional areas were calculated at four equally spaced locations perpendicular to a line drawn from the pubic origin to the visceral insertion using the I-DEAS computer modeling software. RESULTS: The cross-sectional area of the muscle on the side with the defect was smaller than the normal side at all the four locations. The average bilateral difference was up to 81% at location 1 (nearest pubic origin). Almost all of the volume difference (13.7%, P=0.0004) was attributable to a reduction in the pubic portion (24.6%, P<0.0001), not the iliococcygeal portion (P=0.64), of the muscle. CONCLUSIONS: A method was developed to quantify cross-sectional area of the pubic portion of the levator ani perpendicular to the intact muscle direction. Significant bilateral cross-sectional area differences were found between intact and defective muscles in women with a unilateral defect.

Selecting suspension points and excising the vagina during Michigan four-wall sacrospinous suspension.

OBJECTIVE: To describe the variations in the location of the vaginal apex and the length of vagina excised in women undergoing the Michigan four-wall sacrospinous suspension for posthysterectomy vaginal vault prolapse. METHODS: A prospective observational study of 76 women who had the Michigan modification sacrospinous suspension performed between 1998 and 2001 for posthysterectomy vaginal vault prolapse was carried out. Demographics and preoperative, operative, and postoperative findings were noted, including the pelvic organ prolapse quantification score. The locations of the suspension points relative to the hysterectomy scar were recorded. The amount of vagina excised at surgery and the pre- and postoperative vaginal lengths are reported. RESULTS: The mean length and standard deviation of vagina excised was 4.6 +/- 2.5 cm. The apex created at sacrospinous fixation was at the hysterectomy scar in only seven women (9%). It was most often situated behind the hysterectomy scar, in 58 cases (76%); it was situated in front of it in 11 (14%). In seven women no vagina was excised, and in the remaining 69 women a mean length of 5.1 +/- 2.2 cm was removed. The mean vaginal lengths were 9.7 +/- 1.7 cm preoperatively and 9.4 cm +/- 0.8 postoperatively, a 0.3-cm difference. CONCLUSION: When one performs the Michigan modification sacrospinous suspension, the chosen suspension points are often not at the hysterectomy scar, and in women with large prolapses excess vagina frequently is excised without compromising postoperative vaginal length.

Differences in pelvic floor area between African American and European American women.

OBJECTIVE: This study tests the null hypothesis that the size of the pelvic opening spanned by the pelvic floor is the same in African American and European American women. STUDY DESIGN: Forty African American female pelvises were age matched with 40 European American female pelvises from the Hamann-Todd collection at the Cleveland Museum of Natural History. The distances between the anchoring points of the pelvic floor to the bony pelvis (pubis anteriorly, ischial spines laterally, and inferior lateral angle of the sacrum posteriorly) were measured on each half of the pelvis. Measurements from left and right halves were averaged. The cross-sectional area of the pelvic floor was calculated from these dimensions. The bi-ischial line divided the total area into anterior and posterior pelvic floor areas. Analyses taking into account differences in stature by dividing individual dimensions by height were also performed. Group differences were compared with the Student t test and the Mann-Whitney rank sum test. RESULTS: African American women had a 5.1% smaller pelvic floor area than European American women (889.6 cm(2) vs 937.0 cm(2), 5.1% P =.037). This was attributable to a 10.4% smaller posterior area (365.3 cm(2) vs 407.6 cm(2), 10.4% P =.016), whereas the anterior areas were similar (524.3 cm(2) vs 529.3 cm(2), P =.61). The following measured distances were smaller in African American women: ischial spine to inferior sacral angle (5.4 cm vs 5.9 cm, P =.016) and bi-ischial diameter (10.0 cm vs 10.6 cm, P =.004). These distances remained significant after height was controlled. CONCLUSIONS: In African American women, the posterior pelvic floor area is 10.4% smaller than in European American women, resulting in a 5.1% smaller total pelvic floor area.