The Significance Of Pelvic Floor Imaging Changes Of Urethral Funnel And Internal Sphincter In Patients With Stress Urinary Incontinence

Objective: The purpose of this study is to compare the parameters of the urethral funnel and urethral sphincter in primiparae with stress urinary incontinence(SUI)within postpartum period of 6 ~ 8 weeks via translabial two-dimensional ultrasound and transvaginal three-dimensional ultrasound of pelvic floor,and to analyze the relationship between these parameters and SUI in women.Materials and Methods: We randomly selected 2,198 cases of primiparae with single term vaginal delivery within postpartum period of 6 ~ 8 weeks,who visited the Female Pelvic Floor Urinary Reconstructive Center in Dalian Municipal Women and Children’s Medical Center from January 2017 to January 2018.We collected basic information including age,height,weight,body mass index(BMI),and neonatal birth weight etc.According to the symptoms of SUI,they were divided into two groups: group with SUI and group without SUI;and according to the formation of urethral funnel,they were further divided into 4 groups: group A(493 cases),with symptoms of SUI and urethral funnel formation;group B(188 cases),with symptoms of SUI but without urethral funnel formation,group C(540 cases),with urethral funnel formation but without symptoms of SUI and group D(977 cases)with neither symptoms of SUI nor urethral funnel formation.Retrospective analysis was performed on the ultrasonic measurements of the pelvic floor of the 4 groups.We analyzed the formation of urethral funnel and the relative parameters among the groups via translabial two-dimensional ultrasound in states of resting and Valsalva maneuver.The parameters involved the presence or absence of urethral funnel formation,the width,depth and angle of the urethral funnel.We compared the difference of the internal urethral sphincter among the groups via transvaginal threedimensional ultrasound.The parameters involved the length,thickness,area and volume of the internal urethral sphincter.Results: 1.The rate of urethral funnel formation in group with SUI was significantly higher than that in group without SUI(72% vs 36%,P<0.001).2.In both states of resting and Valsalva maneuver,the depth of the urethral funnel in group with SUI was significantly greater than that in group without SUI(rest: 3.01±1.16 vs 3.92±1.51;Valsalva: 4.23±2.04 vs 3.92±1.51,P<0.05,unit: mm).3.In Valsalva state,the angle of the urethral funnel apex in group with SUI was significantly smaller than that in group without SUI(95.94±20.76 vs 99.83±22.11,P<0.05,unit: °).4.The length,thickness,area and volume of the urethral sphincter in group A were significantly smaller than those in group B(length: 16.54±2.93 vs 17.76±2.66,P=0.029;thickness: 3.61±1.16 vs 4.01±0.87,P=0.031;area: 0.68±0.24 vs 0.77±0.15,P=0.049;volume: 1.18±0.46 vs 1.37±0.36,P=0.044,unit: mm).5.The length,thickness,area and volume of the urethral sphincter in group C were all smaller than those in group D(length: 17.21±6.59 vs 18.09±2.71,P=0.019;thickness: 3.86±0.89 vs 4.38±0.80,P=0.045;area: 0.72±0.24 vs 0.83±0.19,P=0.001;volume: 1.25±0.64 vs 1.48±0.44,P=0.003,unit: mm).6.Increased urethral funnel depth in states of resting and Valsalva maneuver is a risk factor of SUI and has statistical significance(resting state: OR=1.135,95%CI 1.015 ~ 1.268;Valsalva state: OR=1.048,95%CI 1.005 ~ 1.135,P<0.05).7.The area under the ROC curve of the depth of the urethral funnel in resting state for the diagnosis of stress urinary incontinence was 0.573(95% CI 0.530 ~ 0.616).And when set the critical value as 2.85 mm,the diagnostic sensitivity of this parameter for SUI is 59.5% and the specificity is 52.7%;the area under the ROC curve of the depth of the urethral funnel in Valsalva state for the diagnosis of stress urinary incontinence is 0.538(95% CI 0.510 ~ 0.581).And when set the critical value as 3.61 mm,the diagnostic sensitivity of this parameter for SUI is 62.5% and the specificity is 54.4%.Conclusion: Pelvic floor ultrasound can dynamically evaluate the anatomical structure of the pelvic floor of SUI patients,which is a simple,economical,practical and non-invasive imaging method.Urethral funnel formation is a characteristic change of female stress urinary incontinence,which may be related to the morphological change of urethral sphincter.The increased depth of urethral funnel is a risk factor for SUI.Pelvic floor ultrasound has a value in predicting the occurrence of stress urinary incontinence.