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.