Applicability of Deep Learning to Dynamically Identify the Different Organs of the Pelvic Floor in the Midsagittal Plane.

INTRODUCTION AND HYPOTHESIS: The objective was to create and validate the usefulness of a convolutional neural network (CNN) for identifying different organs of the pelvic floor in the midsagittal plane via dynamic ultrasound. METHODS: This observational and prospective study included 110 patients. Transperineal ultrasound scans were performed by an expert sonographer of the pelvic floor. A video of each patient was made that captured the midsagittal plane of the pelvic floor at rest and the change in the pelvic structures during the Valsalva maneuver. After saving the captured videos, we manually labeled the different organs in each video. Three different architectures were tested-UNet, FPN, and LinkNet-to determine which CNN model best recognized anatomical structures. The best model was trained with the 86 cases for the number of epochs determined by the stop criterion via cross-validation. The Dice Similarity Index (DSI) was used for CNN validation. RESULTS: Eighty-six patients were included to train the CNN and 24 to test the CNN. After applying the trained CNN to the 24 test videos, we did not observe any failed segmentation. In fact, we obtained a DSI of 0.79 (95% CI: 0.73 - 0.82) as the median of the 24 test videos. When we studied the organs independently, we observed differences in the DSI of each organ. The poorest DSIs were obtained in the bladder (0.71 [95% CI: 0.70 - 0.73]) and uterus (0.70 [95% CI: 0.68 - 0.74]), whereas the highest DSIs were obtained in the anus (0.81 [95% CI: 0.80 - 0.86]) and levator ani muscle (0.83 [95% CI: 0.82 - 0.83]). CONCLUSIONS: Our results show that it is possible to apply deep learning using a trained CNN to identify different pelvic floor organs in the midsagittal plane via dynamic ultrasound.

The Application of Shear Wave Elastography to Determine the Elasticity of the Levator Ani Muscle and Vaginal Tissue in Patients With Pelvic Organ Prolapse.

OBJECTIVES: The changes of the extracellular matrix of the connective tissue have significantly contributed to the incidence of pelvic organ prolapse (POP). It seems reasonable that sonoelastography could be a useful tool to evaluate the elasticity of pelvic floor tissue in patients with POP and compare it to those without POP. The main aim of this pilot study was to determine if there are differences in the elasticity of the levator ani muscle (LAM) and vaginal tissue between patients with and without POP. METHODS: Prospective observation study, including 60 patients (30 with POP and 30 without POP). Sonoelastography was performed to evaluate the elasticity (in kilopascals, kPa) of the following regions of interest: vagina at the level of middle third of the urethra; vagina at the level of the bladder trigone; vagina in the anterior and posterior fornix; vagina at the level of middle third of the anorectal canal; posterior third of the LAM. RESULTS: A total of 60 patients completed the study (30 with POP, 30 without POP). In the POP group, 18/30 (60%) had an anterior vaginal wall prolapse, 3/30 (10%) a uterine prolapse, 15/30 (50%) a rectocele, and 6/30 (20%) a enterocele. Patients with POP had higher elasticity in all anatomical study areas, with statistically significant differences in the anterior fornix (13.6 vs 11.2 kPa; P: .012). A multiple regression (controlling age, menopausal stage, and parity) allowed to detect statistically significant differences in the elasticity of the middle third of the urethra (P: .03) and the middle third of the anorectal canal (P: .019). CONCLUSION: It is possible to evaluate the elasticity of the LAM and vaginal tissue using sonoelastography, detecting a higher elasticity in patients with POP than in those without POP.

Is the Presence of Levator Ani Muscle Avulsion Relevant for the Diagnosis of Uterine Prolapse?

OBJECTIVE: To determine if the addition of the assessment of levator ani muscle (LAM) avulsion to the measurement of the difference in the pubis-uterine fundus distance between rest and with the Valsalva maneuver could increase the diagnostic capacity of ultrasound for uterine prolapse (UP). METHODS: This multicenter, observational and prospective study included 145 patients. Ultrasound assessment was performed, establishing the diagnosis of UP as a difference between the pubic-uterine fundus distance at rest and during the Valsalva maneuver ≥15 mm (standard technique), while LAM avulsion was defined as an abnormal LAM insertion in three central slices using multislice ultrasound. A binary multivariate logistic regression model was made using nonautomated methods to predict surgical UP (general population, premenopausal, and postmenopausal patients), including the difference between the pubis-uterine fundus distance at rest and with the Valsalva maneuver as well as LAM avulsion. RESULTS: A total of 143 patients completed the study. The addition of LAM avulsion criteria to the standard dynamic distance-based protocol for the diagnosis of UP resulted in a higher sensitivity for the general population (79.7 vs 68.1%) as well as for premenopausal (89.3 vs 79.9%) and postmenopausal patients (76 vs 66.1%). In contrast, the standard technique showed a higher specificity than the model based on the standard technique associated with LAM avulsion for the general population (89.2 vs 74.3%) and premenopausal women (91.7 vs 63.2%). For postmenopausal patients, the model based on the standard technique associated with LAM avulsion had a higher sensitivity (76 vs 66.1%) and specificity (91.7 vs 86.8%) than the ultrasound diagnosis of UP. CONCLUSION: The implementation of the assessment of LAM avulsion in the ultrasound diagnosis of UP is useful in postmenopausal patients, increasing sensitivity and specificity relative to the ultrasound assessment based only on the difference between the pubis-uterine fundus distance at rest and with the Valsalva maneuver.

Identification of Surgical Uterine Prolapse in Premenopausal Patients With Clinical or Ultrasound Criteria? A Multicenter Comparative Study.

OBJECTIVES: It is unknown whether diagnosing uterine prolapse (UP) via ultrasound or surgical criteria is superior. Our objective is to determine whether the diagnostic capacity of ultrasound with surgical criteria differs from that of surgical criteria only. METHODS: This was a multicenter prospective observational study with 54 premenopausal patients with surgical criteria for a dysfunctional pelvic floor pathology who were consecutively recruited for 1 year. Clinical UP with surgical criteria was defined when UP stage II-IV was identified (during pelvic floor consultation), and UP diagnosed by ultrasound with surgical criteria was established when a difference ≥15 mm was found between rest and Valsalva applied to the pubis-uterine fundus. The sensitivity, specificity and positive and negative predictive values were determined to evaluate clinical and ultrasound methodologies as diagnostic tests. RESULTS: UP diagnosed by ultrasound with surgical criteria presented better sensitivity (78.57 vs 35.71%), specificity (92.11 vs 81.58%), positive predictive value (61.83 vs 23.99%), and negative predictive value (96.35 vs 11.37%) than UP diagnosed by surgical criteria only. CONCLUSION: Ultrasound with surgical criteria is superior to surgical criteria alone when diagnosing UP.

Is It Possible to Diagnose Surgical Uterine Prolapse With Transperineal Ultrasound? Multicenter Validation of Diagnostic Software.

OBJECTIVES: To validate an ultrasound software that uses transperineal ultrasound to diagnose uterine prolapse (UP). METHODS: Multicenter, observational and prospective study with 155 patients that had indications for surgical intervention for dysfunctional pelvic floor pathology. Each patient underwent an examination with Pozzi tenaculum forceps was performed in the operating room with the patient anesthetized, followed by surgical correction of stages II-IV UP. Transperineal ultrasound was used to assess the difference in the pubis-uterine fundus measurement. With a multivariate logistic regression binary model (with the measurement ultrasound at rest, the Valsalva maneuver and age) using nonautomated methods to predict UP. With the purpose of evaluating the model, a table with coordinates of the receiver operating characteristic (ROC) curve, after which sensitivity and specificity were assessed. RESULTS: A total of 153 patients were included (73 with a diagnosis of surgical UP). It was obtained from the AUC (0.89) of the probabilities predicted by the model (95% confidence interval, 0.84-0.95; P < .0005). Based on the ROC curve for the model, obtaining a sensitivity of 91.8% and a specificity of 72.7%, values that were superior to those for the clinical exam for surgical UP (sensitivity: 80.8%; specificity: 71.3%). CONCLUSIONS: We validated software that uses transperineal ultrasound of the pelvic floor and patient age to generate a more reliable diagnosis of surgical UP than that obtained from clinical examinations.

Interobserver variability of ultrasound measurements for the differential diagnosis of uterine prolapse and cervical elongation without uterine prolapse.

OBJECTIVES: Our study aims to determine the interobserver variability of different ultrasound measurements (pubis-cervix distance, pubis-uterine fundus distance, and pubis-Douglascul-de-sac distance) previously analyzed for the ultrasound differential diagnosis of uterine prolapse (UP) and cervical elongation CE without UP. MATERIALS AND METHODS: We conducted a prospective observational study with 40 patients scheduled to undergo surgical correction of UP and CE without UP. All patients underwent pelvic floor ultrasound examination by an examiner (E1) who acquired ultrasound images. Using these images, E1 measured the distances for the ultrasound differential diagnosis of UP and CE without UP, and these distances were compared with those measured by the other examiner (E2). Values were analyzed by calculating ICCs with 95% CIs. RESULTS: For UP, excellent reliability was obtained for all measurements except the pubis-Douglascul-de-sac measurement at rest, which was moderate (ICC 0.596; p = 0.028) and for the difference between the pubis-Douglascul-de-sac measurement at rest and during the Valsalva maneuver, which was good (ICC 0.691; p < 0.0005). For CE without UP, interobserver reliability was excellent for all measurements analyzed except the pubis-cervix measurement during the Valsalva maneuver, which was moderate (ICC 0.535; p = 0.052) and for the pubis-Douglascul-de-sac measurement at rest, which was good (ICC 0.768; p < 0.0005). CONCLUSIONS: There is excellent interobserver reliability in measurements of the difference in the distance from the pubic symphysis to the uterine fundus at rest and during the Valsalva maneuver for both UP and CE without UP, which are used for the ultrasound differential diagnosis of UP and CE without UP.

Differential diagnosis of middle compartment pelvic organ prolapse with transperineal ultrasound.

INTRODUCTION AND HYPOTHESIS: The objective was to identify the best parameter (pubis-cervix measurement, pubis-uterine fundus measurement or pubis-pouch of Douglas measurement) on transperineal ultrasound, based on the difference between measurements taken at rest and with the Valsalva maneuver, for presurgical differential diagnosis between uterine prolapse (UP) and cervical elongation (CE) without UP. METHODS: A prospective observational study of 60 consecutively recruited patients who underwent corrective surgery of the middle compartment (UP or CE without UP). A transperineal ultrasound was performed, and the descent of the pelvic organ was measured in relation to the posteroinferior margin of the pubis in the midsagittal plane, referencing the uterine fundus, pouch of Douglas and the cervix at rest and with the Valsalva test. RESULTS: Receiver operating characteristic (ROC) curves were constructed for the three evaluated measures, based on the difference between rest and Valsalva, for the diagnosis of UP. For the pubis-cervix distance, an area under the curve (AUC) of 0.59 was obtained; for the pubis-uterine fundus distance, the AUC was 0.81; and for the pubis-pouch of Douglas distance, the AUC was 0.69. Based on the best AUC (the difference in the pubis-uterine fundus distance at rest and with the Valsalva maneuver), a cut-off point of 15 mm was established for the diagnosis of UP (sensitivity: 75%; specificity: 95%; positive predictive value: 86%; and negative predictive value: 89%). CONCLUSION: A difference of ≥15 mm in the pubis-uterine fundus distance at rest and with the Valsalva maneuver is useful for differentiating UP from CE without UP by ultrasound.

Type of levator ani muscle avulsion as predictor for the disappearance of avulsion.

OBJECTIVES: The objective of our study was to establish whether the type of levator ani muscle (LAM) avulsion diagnosed 6 months after delivery influences the integrity of the LAM at 1 year after delivery and determine its influence on the levator hiatus area. STUDY DESIGN: This observational prospective cohort study included 192 primiparous women with vaginal delivery. Transperineal ultrasound examinations were performed at 6 months and 1 year postpartum. Levator hiatus measurements (anteroposterior diameter, transverse diameter, and area) were performed in the plane of minimal dimensions. Complete avulsion was defined based on maximum contraction in multislice mode. Type I LAM avulsion was present when most lateral fibers of the pubovisceral muscle were observed at its insertion at the pubic level (the arch of the elevator remained intact). Type II LAM avulsion was defined as a complete detachment of the pubovisceral muscle from its insertion at the pubic level. RESULTS: In total, 192 patients were recruited after delivery; 48 patients were diagnosed with complete LAM avulsion, and 13 patients with avulsion did not attend the second ultrasound follow-up at 1 year after delivery. Thirty-five patients with complete LAM avulsion were included in the study. At 6 months after delivery, 51 LAM avulsions were observed in 35 patients (including bilateral LAM avulsion in 16 cases), of which 54.9% were right avulsions and 45.1% left avulsions. Furthermore, 11 (five right and six left) were type I LAM avulsions at the 6-month assessment, and all of these had disappeared 1 year after delivery. However, none of the type II LAM avulsions (23 right and 17 left) observed at 6 months had disappeared at the second ultrasound examination. There were no differences between the LAM areas detected at the first and second ultrasound examinations (10.2 ± 3.3 vs 9.3 ± 1.8; P = .404). CONCLUSIONS: The type of LAM avulsion observed at 6 months after childbirth predicts LAM persistence at 1 year postpartum.

Influence of epidemiological characteristics (age, parity and other factors) in the assessment of healthy uterine cervical stiffness evaluated through shear wave elastography as a prior step to its use in uterine cervical pathology.

PURPOSE: The purpose of this study was to evaluate stiffness changes occurring in the healthy uterine cervix according to age, parity, phase of the menstrual cycle and other factors by shear wave elastography (SWE). METHODS: Evaluations of cervical speed and stiffness measurements were performed in 50 non-pregnant patients without gynaecological pathology using SWE transvaginal ultrasound. We performed the evaluation in the midsagittal plane of the uterine cervix with measurements at 0.5, 1 and 1.5 cm from external cervical os, at both anterior and posterior cervical lips. RESULTS: We evaluated 44 patients by SWE and obtained a total average velocity of 3.48 ± 1.08 m/s and stiffness of 42.39 ± 25.33 kPa. We found differences in speed and stiffness according to the cervical lip and depth evaluated; thus, we observed a velocity of 2.70 m/s at 0.5 cm of depth in the anterior lip and 3.53 m/s at 1.5 cm of depth in the posterior lip (p < 0.05). We observed differences according to parity, obtaining a wave transmission speed of 2.67 m/s and 4.41 m/s at the cervical canal of nulliparous and multiparous patients, respectively (p < 0 0.002). We observed differences according to patient age (from a speed of 2.75 m/s at the cervical canal in the age group of 20-35 years to 5.05 m/s in the age group > 50 years) (p < 0.008). We did not observe differences in speed or stiffness according to the phase of the menstrual cycle, BMI, smoking status or the presence or absence of non-HPV infections. CONCLUSIONS: The wave transmission speed and stiffness of the uterine cervix evaluated by SWE varies according to the cervical lip and depth of the evaluation as well as according to the parity and age of the patient.

A simple model to predict the complicated operative vaginal deliveries using vacuum or forceps.

BACKGROUND: Complicated operative vaginal deliveries are associated with high neonatal morbidity and maternal trauma, especially if the procedure is unsuccessful and a cesarean delivery is needed. The decision to perform an operative vaginal delivery has traditionally been based on a subjective assessment by digital vaginal examination combined with the clinical expertise of the obstetrician. Currently there is no method for objectively quantifying the likelihood of successful delivery. Intrapartum ultrasound has been introduced in clinical practice to help predict the progression and final method of delivery. OBJECTIVE: The aim of this study was to compare predictive models for identifying complicated operative vaginal deliveries (vacuum or forceps) based on intrapartum transperineal ultrasound in nulliparous women. STUDY DESIGN: We performed a prospective cohort study in nulliparous women at term with singleton pregnancies and full dilatation who underwent intrapartum transperineal ultrasound evaluation prior to operative vaginal delivery. Managing obstetricians were blinded to the ultrasound data. Intrapartum transperineal ultrasound (angle of progression, progression distance, and midline angle) was performed immediately before instrument application, both at rest and concurrently with pushing. Intrapartum evaluation of fetal biometric parameters (estimated fetal weight, head circumference, and biparietal diameter) was also carried out. An operative vaginal delivery was classified as complicated when 1 or more of the following complications occurred: ≥3 tractions needed; third- to fourth-degree perineal tear; severe bleeding during episiotomy repair (decrease of ≥2.5 g/dL in the hemoglobin level); or significant traumatic neonatal lesion (subdural-intracerebral hemorrhage, epicranial subaponeurotic hemorrhage, skeletal injuries, injuries to spine and spinal cord, or peripheral and cranial nerve injuries). Six predictive models were evaluated (information available in Table 2). RESULTS: We recruited 84 nulliparous patients, of whom 5 were excluded because of the difficulty of adequately evaluating the biparietal diameter and head circumference. A total of 79 nulliparous patients were studied (47 vacuum deliveries, 32 forceps deliveries) with 13 cases in the occiput-posterior position. We identified 31 cases of complicated operative vaginal deliveries (19 vacuum deliveries and 12 forceps deliveries). No differences were identified in obstetric, neonatal, or intrapartum characteristics between the 2 study groups (operative uncomplicated vaginal delivery vs operative complicated vaginal delivery), with the following exceptions: estimated fetal weight (3243 ± 425 g vs 3565 ± 330 g; P = .001), biparietal diameter (93.2 ± 2.1 vs 95.2 ± 2.3 mm; P = .001), head circumference (336 ± 12 vs 348 ± 6.4 mm; P = .001), sex (female 62.5% vs 29.0%; P = .010), newborn weight (3258 ± 472 g vs 3499 ± 383 g; P = .027), and number of tractions (median, interquartile range) (1 [1-2] vs 4 [3-5]; P < .0005). To predict complicated operative deliveries, all 6 of the studied models presented an area under the receiver-operating characteristics curve between 0.863 and 0.876 (95% confidence intervals, 0.775-0.950 and 0.790-0.963; P < .0005). The results of the study met the criteria of interpretability and parsimony (simplicity), allowing us to identify a binary logistic regression model based on the angle of progression and head circumference; this model has an area under the receiver-operating characteristics curve of 0.876 (95% confidence interval, 0.790-0.963; P < .0005) and a calibration slope B of 0.984 (95% confidence interval, 0.0.726-1.243; P < .0005). CONCLUSION: The combination of the angle of progression and the head circumference can predict 87% of complicated operative vaginal deliveries and can be performed in the delivery room.

Influence of the disengagement of the forceps on levator ani muscle injuries in instrumental delivery: A multicenter study.

INTRODUCTION: Forceps use is the main risk factor for levator ani muscle (LAM) injuries. We believe that the disengagement of the forceps branches before delivery of the fetal head could influence LAM injuries, so we aimed to determine the influence of the disengagement of the forceps on the occurrence of LAM avulsion during forceps delivery. MATERIAL AND METHODS: A prospective, observational, multicenter study was conducted with 261 women who underwent forceps delivery. The women were classified according to whether the branches of the forceps had been disengaged before delivery of the fetal head. LAM avulsion was defined using a multislice mode (3 central slices). RESULTS: In all, 255 women completed the study (160 without disengagement and 95 with disengagement). LAM avulsions were observed in 37.9% of women in the group with disengagement and in 41.9% of women in the group without disengagement. The crude OR (without disengagement vs with disengagement) for avulsion was 0.90 (95% CI 0.49-1.67, P = 0.757) and an adjusted OR of 0.82 (95% CI 0.40-1.69, P = 0.603). CONCLUSIONS: We did not observe a statistically significant reduction in the LAM avulsion rate with disengagement of the forceps branches before delivery of the fetal head.

The correlation between the type of forceps application and the rate of levator ani muscle avulsion: A prospective cohort study.

OBJECTIVES: The association between the use of forceps and levator ani muscle (LAM) avulsion seems to be clear-cut. However, whether the lesion is due to the mechanical trauma yielded by the instrument or to the intrinsic complexity of this type of delivery, is yet to be determined. This study aims at determining the difference in LAM avulsion rate between Kielland rotational forceps and non-rotational forceps. STUDY DESIGN: Prospective observational study with 94 nulliparous women with forceps-assisted deliveries (FD) between July 2015 and January 2016. 3D-TpUS was performed 6 months after every patient's delivery, during which LAM avulsion, and levator hiatus area and anteroposterior and transverse diameters were assessed. RESULTS: A total of 89 nulliparous were studied, comprising 27 rotational-FD, and 62 non-rotational-FD. No differences in obstetric, intrapartum, or neonatal characteristics were observed between study groups. There were no statistically significant differences in the presence of avulsion between cases of rotational forceps (44.4% vs 35.5%, OR: 1.5 [0.6-3.6]), correction of asinclitism of the fetal head (34.4% vs. 40.4% OR: 0.8 [0.3-1.9]) or station (midforceps: 32.8% vs low forceps: 50.0% OR: 2.0 [0.8-5.1]). CONCLUSIONS: We have not observed differences in the LAM-avulsion rate between rotational forceps and non-rotational forceps performed by highly experienced personnel in instrumental deliveries.

Evaluation of levator ani muscle throughout the different stages of labor by transperineal 3D ultrasound.

OBJECTIVE: Description and assessment by 3-D transperineal ultrasound of modifications suffered by pelvic floor muscles during the passage of the fetal head through the birth canal during the second stage of labor, as well as the identification of the precise moment in which levator ani muscle avulsion takes place. MATERIALS AND METHODS: Patients included were 35 primigravidae, recruited during the first stage of labor, with at term pregnancy (37-42 weeks), without serious maternal-fetal pathology and cephalic presentation. A prospective observational study of 35 primigravidae, recruited during the first stage of labor, with at term pregnancy (37-42 weeks), with fetus in cephalic presentation and without serious maternal-fetal pathology. Sonographic evaluation was carried out by 3-D transperineal ultrasound during the first and second stages of labor (with fetal head in 1st, 2nd-3rd and 4th planes of Hodge), immediately postpartum and 6 months postpartum. Ultrasound parameters studied were antero-posterior and transverse diameters, as well as levator hiatus area and levator ani muscle thickness and area. RESULTS: Twenty-one patients were studied (15 spontaneous deliveries; 6 instrumental deliveries). When measured with fetal head in the 4th plane of Hodge, a significant increase both in the levator hiatus area (15.39 cm2 /15.68 cm2 /20.96 cm2 /42.55 cm2 /22.92 cm2 /18.18 cm2 ; P < 0.0005) and in the levator ani muscle area (8.78 cm2 /9.18 cm2 /9.69 cm2 /15.07 cm2 /11.33 cm2 /12.36 cm2 ; P < 0.0005) was identified. Four cases of unilateral right avulsion (two vacuum and two forceps deliveries) were identified. CONCLUSIONS: We conclude that the phase of delivery that causes a major increase in the area of the levator hiatus area and in the levator ani muscle area is when the fetal head reaches the 4th plane of Hodge. Furthermore, data in our paper indicates that the exact moment in which the avulsion of the levator ani muscle is produced is when the bulging of the fetal head on the maternal perineum occurs.

Evaluation of isolated urinary stress incontinence according to the type of levator ani muscle lesion using 3/4D transperineal ultrasound 36 months post-partum.

INTRODUCTION: Vaginal delivery can lead to pelvic floor disorders. Many authors have described pelvic floor injuries that can predict future defects such as urinary incontinence and pelvic organ prolapse. We propose the assessment of urinary stress incontinence and its association with levator ani muscle (LAM) microtrauma (>20% in the levator hiatus area during Valsalva) and macrotraumas (avulsion) identified by 3/4D transperineal ultrasound (3D-TpUS) 36 months post-partum. MATERIALS AND METHODS: This was a prospective observational study including 168 nulliparous women. All patients included were nulliparous with singleton gestation in cephalic presentation, at ≥37 weeks and were recruited on the first day after delivery. Thirty-six months after delivery, 3D-TpUS was carried out to identify LAM lesions (macro or micro). Clinical assessment of urinary stress incontinence (USI) was based on the ICIQ-UI-SF test; a simple stress test and urodynamic test were carried out in the same visit. RESULTS: A total of 105 nulliparous women were studied (51 spontaneous deliveries [SpD] and 54 vacuum-assisted deliveries [VD]). Microtraumas were identified in 35.3% of SpD and 20.4% of VD. Macrotraumas (avulsion) were identified in 9.8% of SpD and 35.2% of VD (p = 0.006). No differences were found in USI between study groups or in relation to the identification of LAM defects (19.2% in the no lesion group, 25% in the macrotrauma and 13.8% in the microtrauma groups; p = not significant). Nor were significant differences found in the results from the different study groups in the International Consultation on Incontinence Modular Questionnaire Urinary Incontinence Short Form (ICIQ-UI SF) test (12.7±2.2 in the no lesion group, 12.5±4.2 in the macrotrauma and 13.25±4.8 in the microtrauma groups; p = NS). CONCLUSION: No difference was observed in USI between patients with and without LAM lesions (microtrauma or macrotrauma) 36 months post-delivery.

Multicenter study of the evolution of different types of avulsion over the 12 months after delivery.

OBJECTIVE: To perform a multicenter study of muscle recovery in levator ani muscle (LAM) avulsion during the first 12 months postpartum according to the type of LAM avulsion suffered. METHODS: This was a multicenter prospective observational study including 242 primiparas. Transperineal ultrasound was performed at 6 months and 12 months after delivery. Type I LAM avulsion was present when most of the lateral fibers of the pubovisceral muscle were observed at the muscle's insertion at the pubic level. Type II LAM avulsion was defined as complete detachment of the pubovisceral muscle from its insertion at the pubic level. RESULTS: Among the 56 patients who completed the study (with ultrasound at 6 and 12 months after delivery), 76 avulsions (10 cases of bilateral avulsion) were identified at 6 months after delivery, and the total number of avulsions had decreased to 58 at 12 months after delivery (P < 0.001; 95% confidence interval [CI] 13.9%-33.5%). This decrease was due to the disappearance of 69.2% of the cases of Type I LAM avulsions (P < 0.001; 95% CI: 50.2%-88.2%). However, the number of Type II LAM avulsions remained constant at 6 months and 12 months after delivery. CONCLUSION: The spontaneous resolution of LAM avulsion during the first 12 months postpartum occurs in cases of Type I LAM avulsion but is not observed in Type II LAM avulsion.

Can Intrapartum Ultrasonography Improve the Placement of the Vacuum Cup in Operative Vaginal Deliveries?

Although the fetal head position has traditionally been evaluated by digital examination (DE), it has a failure rate ranging between 20 and 70%; hence, intrapartum transabdominal ultrasonography (TUS) has become relevant. We aimed to evaluate the utility of the TUS to identify the fetal head positions in vacuum-assisted deliveries. We performed a prospective observational study including 101 pregnant patients in active labor who required a vacuum-assisted delivery. The fetal head position was assessed by a DE and a TUS prior to vacuum cup placement. After delivery, the optimal vacuum cup placement was evaluated as the distance between the chignon and the flexion point ≤2 cm. The general concordance rate between the DE and TUS was 72.2%, with the poorest concordance rate for occiput posterior positions at 46.1%. In five cases (4.9%), it was not possible to determine the fetal head position through the DE. The correlation was higher in low and medium planes, with 77% and 68.1% concordance rates, respectively, while it was lower in high planes (60%). In 90.1% of cases, the vacuum cup placement was optimal. Our findings show that intrapartum transabdominal ultrasonography is a useful technique to identify the fetal head position allowing optimal placement of the vacuum cup necessary for correct vacuum-assisted delivery.

Assessment of late on-set fetal growth restriction using SMI (superb microvascular imaging) Doppler.

Background: The identification of late-onset fetal growth restriction (FGR) fetuses remains a challenge, given the difficulty to distinguish them from healthy small for gestational age (SGA) fetuses. Given the limitations of conventional Doppler for the identification of placental insufficiency, the appearance of superb microvascular imaging (SMI) Doppler seems promising. Our main objective was to evaluate the diagnostic capability of SMI Doppler for the detection of placental insufficiency findings. Methods: A prospective observational study was conducted at a tertiary care center, including 51 patients who had been diagnosed with late on-set SGA or FGR. A placental ultrasonographic evaluation was carried out using SMI Doppler. Patients were sorted into two groups attending to the histologic evaluation of the placentas after delivery: Group 1 (21 cases), Normal group; and Group 2 (30 cases), FGR group. Results: Placentas in the FGR group had lower peak systolic velocity (PV) values of the chorionic plate. The PV of the other vessels were consistently lower in the FGR group that in the normal group, although without reaching statistical significance. Conclusions: The PV of the chorionic plate measured with SMI Doppler, have the capacity to identify placental insufficiency findings. Ultrasonographic placental assessment using SMI Doppler appears to be a useful technique for the evaluation of suspected late on-set placental insufficiency.

Reproducibility of the anorectal angle with transperineal ultrasound.

Background: The anorectal angle (ARA) has been assessed with different imaging methods and its measurement has traditionally been based on defecography or magnetic resonance studies. Different ultrasound methodologies have also been used for ARA assessment and have been validated as alternatives for the ARA measurement, such as three-dimensional (3D) endovaginal ultrasound and 3D transperineal ultrasound. 3D transperineal ultrasound does not require the introduction of ultrasound transducers inside the anal canal. Therefore, it is reasonable to think that the use of transperineal ultrasound can provide more reproducible ARA measurements, something that has not been established by 3D endovaginal probe or defecography. Our objective is to determine the intraobserver and interobserver variability of transperineal ultrasound for the assessment of ARA. Methods: A retrospective observational study was performed with 40 patients. The study of the ARA was performed from the mid-sagittal plane (at rest, Valsalva and maximum contraction), visualizing the anorectal canal, the anorectal junction and the rectal ampulla. ARA measurements were performed initially by explorer 1 (E1), subsequently by explorer 2 (E2) and finally again by E1. Intraobserver and interobserver variability was calculated by calculating the intraclass correlation coefficient (ICC) with 95% confidence interval (CI). Results: Intraobserver variability was excellent for all measurements of the ARA at rest, Valsalva and maximal contraction, with ICC ranging from 0.968 to 0.975. Interobserver variability was also superb for all measurements of the ARA at rest, Valsalva and maximal contraction, with ICC ranging from 0.971 to 0.979. Conclusions: Intraobserver and interobserver variability were excellent for the ARA measurements by transperineal ultrasound.

The Role of Transperineal Ultrasound for the Assessment of the Anorectal Angle and Its Relationship with Levator Ani Muscle Avulsion.

The relationship between the anorectal angle (ARA) and the levator ani muscle (LAM) is well known. In this study, we aimed to demonstrate that the ARA changes when LAM avulsion occurs after vaginal delivery. This was a secondary, observational retrospective study with data obtained from three previous studies. Using transperineal ultrasound, the presence of avulsion was assessed when abnormal insertion of the LAM was observed in three central slices. In addition, the ARA was assessed in the midsagittal plane (at rest, in Valsalva and at maximum contraction) as the angle between the posterior border of the distal part of the rectum and the central axis of the anal canal. The ARA was higher in patients with bilateral LAM avulsion than in patients without LAM avulsion at rest (131.8 ± 14.1 vs. 136.2 ± 13.8), in Valsalva (129.4 ± 15.5 vs. 136.5 ± 14.4) and at maximum contraction (125.7 ± 15.5 vs. 132.3 ± 13.2). The differences between both groups expressed as the odds ratio (OR) adjusted for maternal age were 1.031 (95% confidence interval (CI), 1.001-1.061; p = 0.041) at rest, 1.036 (95% CI, 1.008-1.064; p = 0.012) in Valsalva and 1.031 (95% CI, 1.003-1.059; p = 0.027) at maximum contraction. In conclusion, LAM avulsion produces an increase in the ARA at rest, during contraction and in Valsalva, especially in cases of bilateral LAM avulsion.