Comparing the diagnostic accuracy of 3 ultrasound modalities for diagnosing obstetric anal sphincter injuries.

BACKGROUND: The optimal imaging modality of obstetric anal sphincter injuries needs to take into consideration convenience, availability, and ability to assess the sphincter morphologic condition. Endoanal ultrasound imaging currently is regarded as the reference standard, but it is not widely available in obstetric units. Exoanal alternatives exist, such as 3-dimensional introital or transperineal ultrasound imaging, which are already readily available in most obstetrics and gynecology units. OBJECTIVE: The primary objective was to evaluate the diagnostic accuracy of 3-dimensional introital and 3-dimensional transperineal ultrasound imaging compared with 3-dimensional endoanal ultrasound imaging as the reference standard for the detection of anal sphincter defects in women who sustained obstetric anal sphincter injuries. The secondary objective was to correlate a diagnosis of anal sphincter defect on imaging to symptoms of anal incontinence, and to assess patient discomfort that is experienced for each imaging modality. STUDY DESIGN: A cross-sectional study was conducted of 250 women who sustained obstetric anal sphincter injuries, all of whom underwent 3-dimensional introital, transperineal, and endoanal ultrasound imaging. Introital and transperineal ultrasound imaging were assessed with tomographic ultrasound imaging. All of the women completed a validated modified St Mark's Score and Visual Analogue Score for discomfort. Optimal cut-off values for a significant defect on tomographic ultrasound imaging were defined as those with the greatest sensitivity and specificity based on receiver operating characteristic curves with endoanal ultrasound imaging as the reference standard. Diagnostic test characteristics of introital and transperineal ultrasound imaging were calculated with the use of these optimal cut-offs. RESULTS: Optimal cut-off for a significant external anal sphincter defect was ≥3 of 7 slices; sensitivity and specificity were 0.65 and 0.75 on introital imaging and 0.70 and 0.69 on transperineal ultrasound imaging. Optimal cut-off for a significant internal anal sphincter defect was ≥2 of 5 slices; sensitivity and specificity were 0.59 and 0.84 on introital imaging and 0.43 and 0.97 on transperineal ultrasound imaging. The area under the curve for the diagnosis of external and internal anal sphincter defects ranged from 0.70-0.74 (P<.001) for introital and transperineal imaging. Positive predictive value for external and internal sphincter defects ranged from 0.37-0.63, and negative predictive value ranged from 0.85-0.93 for introital and transperineal ultrasound imaging. Endoanal ultrasound imaging was the only modality for a defect to correlate with symptoms; mean modified St. Mark's score for a defect sphincter was 2.4 (standard deviation, 4.1) and for an intact sphincter was 0.9 (standard deviation, 2.7; P<.01). Introital and transperineal ultrasound imaging were associated with less discomfort than endoanal ultrasound imaging. CONCLUSION: Endoanal ultrasound imaging remains the most accurate diagnostic imaging modality. With low positive predictive values, introital and transperineal ultrasound imaging are not suitable for the identification of sphincter defects; however, high negative predictive values show a good ability to detect an intact sphincter. The optimal cut-off number of slices on tomographic ultrasound imaging for external and internal anal sphincters allows for standardization of a significant defect. In women with a history of obstetric anal sphincter injuries, introital and transperineal ultrasound imagings are suitable to screen for an intact sphincter if endoanal ultrasound imaging is not available. When defects are found, women should then have endoanal ultrasound imaging to verify the diagnosis.

Accuracy of Four Imaging Techniques for Diagnosis of Posterior Pelvic Floor Disorders.

OBJECTIVE: To establish the diagnostic test accuracy of evacuation proctography, magnetic resonance imaging (MRI), transperineal ultrasonography, and endovaginal ultrasonography for detecting posterior pelvic floor disorders (rectocele, enterocele, intussusception, and anismus) in women with obstructed defecation syndrome and secondarily to identify the most patient-friendly imaging technique. METHODS: In this prospective cohort study, 131 women with symptoms of obstructed defecation syndrome underwent evacuation proctogram, MRI, and transperineal and endovaginal ultrasonography. Images were analyzed by two blinded observers. In the absence of a reference standard, latent class analysis was used to assess diagnostic test accuracy of multiple tests with area under the curve (AUC) as the primary outcome measure. Secondary outcome measures were interobserver agreement calculated as Cohen's κ and patient acceptability using a visual analog scale. RESULTS: No significant differences in diagnostic accuracy were found among the imaging techniques for all the target conditions. Estimates of diagnostic test accuracy were highest for rectocele using MRI (AUC 0.79) or transperineal ultrasonography (AUC 0.85), for enterocele using transperineal (AUC 0.73) or endovaginal ultrasonography (AUC 0.87), for intussusception using evacuation proctography (AUC 0.76) or endovaginal ultrasonography (AUC 0.77), and for anismus using endovaginal (AUC 0.95) or transperineal ultrasonography (AUC 0.78). Interobserver agreement for the diagnosis of rectocele (κ 0.53-0.72), enterocele (κ 0.54-0.94) and anismus (κ 0.43-0.81) was moderate to excellent, but poor to fair for intussusception (κ -0.03 to 0.37) with all techniques. Patient acceptability was better for transperineal and endovaginal ultrasonography as compared with MRI and evacuation proctography (P<.001). CONCLUSION: Evacuation proctography, MRI, and transperineal and endovaginal ultrasonography were shown to have similar diagnostic test accuracy. Evacuation proctography is not the best available imaging technique. There is no one optimal test for the diagnosis of all posterior pelvic floor disorders. Because transperineal and endovaginal ultrasonography have good test accuracy and patient acceptability, we suggest these could be used for initial assessment of obstructed defecation syndrome. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02239302.

Macroscopic and microscopic morphology of first trimester miscarriage and subsequent pregnancy outcome - An exploratory study.

INTRODUCTION: Reduced chorionic villous vascularization is associated with first trimester miscarriage and second trimester fetal loss. Differences in villous vascularization have been observed in combination with complications in the third trimester of pregnancy. The aim of this study was to investigate whether abnormal morphology and reduced chorionic villous vascularization in first trimester miscarriages are associated with an increased risk on adverse outcome and/or pregnancy complications in subsequent pregnancy. Secondly, to assess the influence of these parameters on the length of the interpregnancy interval and infertility. METHODS: In a retrospective cohort study 134 consecutive women who underwent dilatation and curettage for a miscarriage were included. The degree of chorionic villous vascularization in miscarriage tissue was determined by a pathologist. Ultrasound details of these miscarriages and clinical data on the subsequent pregnancy of these women were obtained. RESULTS: Neither reduced vascularization nor early embryonic arrest in first trimester miscarriages are associated with an increased risk of a subsequent miscarriage or adverse obstetric and perinatal outcome of subsequent pregnancy. Abnormal morphology of the first trimester miscarriage did not influence the time to subsequent pregnancy. A shorter mean interpregnancy interval between miscarriages was observed after miscarriages with reduced chorionic villous vascularization (5.5 vs. 10.7 months; p = 0.051), showing a trend towards an association. DISCUSSION: Chorionic villous vascularization and morphology have no influence on subsequent pregnancy outcome. Therefore it remains unknown what aspects of miscarriage are causing the increased risk on subsequent miscarriage and complications in the third trimester of the subsequent pregnancy.

Design and validation of a 3D virtual reality desktop system for sonographic length and volume measurements in early pregnancy evaluation.

PURPOSE: To design and validate a desktop virtual reality (VR) system, for presentation and assessment of volumetric data, based on commercially off-the-shelf hardware as an alternative to a fully immersive CAVE-like I-Space VR system. METHODS: We designed a desktop VR system, using a three-dimensional (3D) monitor and a six degrees-of-freedom tracking system. A personal computer uses the V-Scope (Erasmus MC, Rotterdam, The Netherlands) volume-rendering application, developed for the I-Space, to create a hologram of volumetric data. Inter- and intraobserver reliability for crown-rump length and embryonic volume measurements are investigated using Bland-Altman plots and intraclass correlation coefficients. Time required for the measurements was recorded. RESULTS: Comparing the I-Space and the desktop VR system, the mean difference for crown-rump length is -0.34% (limits of agreement -2.58-1.89, ±2.24%) and for embryonic volume -0.92% (limits of agreement -6.97-5.13, ±6.05%). Intra- and interobserver intraclass correlation coefficients of the desktop VR system were all >0.99. Measurement times were longer on the desktop VR system compared with the I-Space, but the differences were not statistically significant. CONCLUSIONS: A user-friendly desktop VR system can be put together using commercially off-the-shelf hardware at an acceptable price. This system provides a valid and reliable method for embryonic length and volume measurements and can be used in clinical practice.