Comparison of transperineal and endoanal ultrasound in detecting residual obstetric anal sphincter injury

Abstract

Introduction Endoanal ultrasound is considered the gold standard when assessing the obstetric anal sphincter complex. Due to its relative intrusiveness and economic cost, other ultrasound modalities are on the rise, such as transperineal ultrasound with a convex probe. The aim of our study was to evaluate the agreement between endoanal ultrasound scores (EAUS score) and transperineal ultrasound scores (TPUS score) in assessing residual obstetric anal sphincter defects. Material and methods Fifty‐nine women were examined 6 months after primary suturing of obstetric anal sphincter injury with two ultrasound modalities. A standardized scoring system analyzing the length, depth and radial extent of both the external (EAS) and internal (IAS) sphincter was used. Wexner fecal incontinence score was used to assess the patients’ symptoms. Results Transperineal ultrasound scores score showed a strong significant correlation with EAUS score during both pelvic floor relaxation and contraction: Spearman's rho [rs] = 0.74, P < 0.001, and rs = 0.77, P < 0.001, respectively. For both EAS and IAS, significant correlations were found for all parameters, that is, length, depth and angle between both EAUS and TPUS. A statistically significant correlation was found between EAUS score and Wexner score (rs = 0.36, P = 0.005). A significant correlation between the EAS‐EAUS score (rs = 0.36, P = 0.005) and Wexner score was found, but no significance was found between IAS‐EAUS score and Wexner score (rs = 0.22, P = 0.097). Significant correlations were found for Wexner score and TPUS score in resting state (rs = 0.36, P = 0.01) and contracting state (rs = 0.28, P < 0.05), and between Wexner score and EAS‐TPUS score in resting state (rs = 0.32, P = 0.02). Conclusions The results indicated a strong agreement between endoanal and transperineal ultrasound in assessing residual obstetric anal sphincter defects 6 months after primary suturing. Furthermore, a weak significant correlation was found between the ultrasound scores and the patients’ Wexner fecal incontinence score.

Postpartum ultrasound for the diagnosis of obstetrical anal sphincter injury

“…4D-TPUS, performed during maximum anal sphincter contraction at 10-12 weeks after delivery has the potential to replace 3D-EAUS. Good agreement between these two techniques has been demonstrated (27), with a  value of 0.76 for a comparison of 3D-EAUS and 3D-TPUS. (28) 4D imaging of the anal canal has become fully standardized since 2012.…”

Diagnosis and Treatment of Obstetric Anal Sphincter Injuries: New Evidence and Perspectives

“…Even though TPUS has not yet achieved the same results in terms of images quality when compared to the current gold standard technique, more and more studies are observing a good correlation between these two techniques [ 48 ].…”

Correlations of obstetric anal sphincter injury (OASIS) grade, specific symptoms of anal incontinence, and measurements by endoanal and transperineal ultrasound

“…The study group and method are the same as in a previously published article [ 13 ]. All women with OASIS in conjunction with delivery were offered a follow up appointment 6 months after delivery.…”

“…Endoanal ultrasound (EAUS) is considered gold standard in ultrasonographic assessment of OASIS. Other ultrasound modalities are on the rise, recently three-dimensional transperineal ultrasound (TPUS) was presented as a screening tool in assessment of residual defects after OASIS [ 12 ], We have previously showed a strong a correlation between EAUS and TPUS in the assessment of residual defects six months after primary suturing of OASIS [ 13 ], the TPUS score showed a strong correlation with EAUS score during both pelvic floor relaxation and contraction ( r s = 0.74, P < 0.001 and r s = 0.77, P < 0.001, respectively). Significant correlations between EAUS and TPUS were found when assessing the depth, length and angle of the defect, regarding both the EAS and IAS.…”