Dynamic 2-dimensional transperineal ultrasound evaluation in labor room as a screening tool for anal sphincter injuries and anal incontinence in primiparous women

4D transperineal ultrasound: feedback for good obstetric anal sphincter injuries reparation

BACKGROUND

Obstetric anal injury is the main risk factor for traumatic anal, faecal and flatus, incontinence in women in reproductive age. Its recognition and good reparation are crucial for long term outcomes.

CASE REPORT

We report a case of a nulliparous woman who reported a fourth-degree perineal tear after delivery. The obstetric anal sphincter injury was repaired and a four-dimensional transperineal ultrasound was performed after reparation and then one and three months after discharge. The woman did not experience any incontinence and no points of discontinuity were observed at tomographic ultrasound imaging reconstruction. In this case, 4D-TPUS was a tool in the obstetrician's hands to evaluate the surgical success of OASIS repair, which requires some expertise.

CONCLUSIONS

4D-TPUS ultrasound is useful and reliable during immediate puerperium and in the subsequent follow-up, giving positive feedback on the correct positioning of the stiches and on a good healing process. Further studies are needed to demonstrate this usefulness in the operators training and for improving their surgical skills.

Three-Dimensional Transperineal Ultrasound Assessment of the Anal Sphincter Immediately After Vaginal Birth: An Exploratory Study

OBJECTIVES

To assess the feasibility of acquiring adequate transperineal ultrasound (TPUS) volumes of the anal sphincter (AS) immediately after vaginal birth, the reproducibility of its measurements, and detecting defects therein.

METHODS

Secondary analysis of TPUS volumes of the AS, acquired immediately after vaginal birth with a transversely oriented convex probe. Two independent experts ranked off-line image quality as "inadequate," "adequate," or "ideal" using the Point-of-Care Ultrasound Image Quality scale. On "adequate" and "ideal" quality volumes, the length of the external AS at 6 and 12 o'clock, and the volume of the external and internal AS were measured. Additionally, volumes were screened for AS defects on tomographic ultrasound imaging. Subsequently, we rated the intra- and interrater agreement on those findings.

RESULTS

Of 183 volumes, 162 were considered "adequate" or of "ideal" quality (88.5%). Reasons for "inadequacy" were shadow artifacts (16/21), poor resolution (3/21), incomplete acquisition (1/21), or aberrant AS morphology (1/21). The intrarater reliability of two-dimensional (2D) and three-dimensional (3D) measurements was excellent, whereas interrater reliability was fair to good for 2D measurements and good for 3D measurements. In those tomographic ultrasound imaging (TUI) sequences including AS defects, the intra- and interrater reliability of the defect measurement were excellent [intraclass correlation coefficient (ICC) = 0.92 (0.80-0.94)] and moderate [ICC = 0.72 (0.63-0.79)]. In this cohort, there were only few (4/48; 8.3%) AS defects. However, grading them was poorly reproducible between experts.

CONCLUSION

TPUS of the AS immediately after vaginal birth yields adequate image quality and allows for reproducible measurements. In the few patients with AS defects, there was good agreement on the presence, but it was poor for the extent of defects.

Use of endoanal ultrasound in detecting obstetric anal sphincter injury immediately after birth

INTRODUCTION

Obstetric anal sphincter injury (OASI) complicates around 5% of deliveries in primiparas. The study objective was to assess the utility of three-dimensional endoanal ultrasonography (3D-EAUS) in the diagnosis of OASI.

MATERIAL AND METHODS

The present study was designed to mirror screening settings with an unselected cohort of nulliparous women. All enrolled patients underwent clinical examination of the perineum by the caregiver, and 3D-EAUS was conducted. Post-processing of ultrasonography volume data was performed by an experienced colorectal surgeon who was blinded to all other data. The sensitivity, specificity, negative predictive value, and positive predictive value of 3D-EAUS in the diagnosis of OASI was evaluated. The trial is registered at ISCRTN: 18006769.

RESULTS

A total of 680 scans were performed, of which 18.5% were judged as "non-assessable", resulting in 554 assessable recordings. Sphincter defects were observed in 12.8% of all assessable recordings on 3D-EAUS (n = 71). With clinical examination set as the reference standard, ultrasound sensitivity in the diagnosis of OASI was 30.4%, whereas its specificity was 87.9%. The negative predictive value was 96.7% and the positive predictive value was only 9.9%. Comments were left on 175 examinations, of which 74% referred to the management of the examination.

CONCLUSIONS

Using 3D-EAUS in a maternity ward is demanding because staff generally have little experience in endoanal ultrasound, which contributes to difficulties in obtaining good image quality. When 3D-EAUS is performed to mirror screening settings, it adds no convincing diagnostic power to clinical examination in the diagnosis of OASI.

Risk Factors in Third and Fourth Degree Perineal Tears in Women in a Tertiary Centre: An Observational Ambispective Cohort Study

Objectives: To analyze the main risk factors associated with third and fourth degree postpartum perineal tears in women attended to in our obstetrics service. Methods: An observational, retrospective, hospital cohort study was carried out in women whose deliveries were attended to in the obstetrics service of the Hospital General Universitario Gregorio Marañón de Madrid (HGUGM), during the period from January 2010 to April 2017. Results: During the study period, a total of 33,026 patients were included in the study. For maternal variables, the associated increased risk of severe perineal tearing in nulliparous women is OR = 3.48, for induced labor OR = 1.29, and for instrumental delivery by forceps OR = 4.52 or spatulas OR = 4.35; for the obstetric variable of episiotomy, it is OR = 3.41. For the neonatal variables, the weight of the newborns has a directly proportional relationship with the risk of severe tears, and for birth weights of 3000 g (OR = 2.41), 3500 g (OR = 1.97), and 4000 g (OR = 2.17), statistically significant differences were found in each of the groups (p < 0.05). Conclusion: Primiparity, induction of labor, episiotomy, instrumental delivery with forceps or spatula, and a birth weight of 3000 g or more are significantly associated with an increased risk of third and fourth degree perineal tears.

Postpartum ultrasound for the diagnosis of obstetrical anal sphincter injury

This review presents the available data on the diagnosis of obstetrical anal sphincter injury by postnatal ultrasound imaging. There is increasing evidence that anal sphincter tears are often missed after childbirth and, even when diagnosed, often suboptimally repaired, with a high rate of residual defects after reconstruction. Even after postpartum diagnosis and primary repair, 25% to 50% of patients will have persistent anal incontinence. As clinical diagnosis may fail in the detection and classification of obstetrical anal sphincter injury, the use of imaging has been proposed to improve the detection and treatment of these lacerations. Notably, 3-dimensional endoanal ultrasound is considered the gold standard in the detection of obstetrical anal sphincter injury, and recently, 4-dimensional transperineal ultrasound, commonly available in obstetrical and gynecologic settings, has proven to be effective as well. Avoidance of forceps delivery when possible, performance of a rectal examination after vaginal delivery and before repair of any severe perineal tear, and offering sonographic follow-up at 10 to 12 weeks after vaginal delivery in high-risk women (maternal age of ≥35 years, vaginal birth after cesarean delivery, forceps, prolonged second stage of labor, overt obstetrical anal sphincter injury, shoulder dystocia, and macrosomia) may help reduce morbidity arising from anal sphincter tears.

Obstetric anal sphincter injuries: strategies for prevention, diagnosis, and management

Obstetric anal sphincter injuries (OASIS) are one of the most common causes of anal incontinence (AI) in women of reproductive age and can have a significant impact on quality of life. However, many women do not report symptoms to their physicians because of embarrassment and shame. Therefore, prevention and diagnosis of the tear is essential. Diagnostic strategies have evolved considerably in recent years, with an increase in prevalence of OASIS as a consequence. The use of 3D endoanal (3D-EAUS) and 4D transperineal ultrasound (4D-TPUS), in addition to standard clinical examination have enhanced the detection of OASIS. Once identified, adequate repair by a skilled practitioner and optimal postpartum management should be ensured in order to reduce the risk of anal incontinence. This review presents the available evidence on strategies for prevention, diagnosis, and management of OASIS.