Pelvic floor ultrasonography: an update

Female pelvic floor dysfunction encompasses a number of highly prevalent clinical conditions such as female pelvic organ prolapse, urinary and fecal incontinence, and sexual dysfunction. The etiology and pathophysiology of those conditions are, however, not well understood. Recent technological advances have seen a surge in the use of imaging, both in research and clinical practice. Among the techniques available such as sonography, X-ray, computed tomography and magnetic resonance imaging, ultrasound is superior for pelvic floor imaging, especially in the form of perineal or translabial imaging. The technique is safe with no radiation, simple, cheap, easily accessible and provides high spatial and temporal resolutions. Translabial or perineal ultrasound is useful in determining residual urinary volume, detrusor wall thickness, bladder neck mobility and in assessing pelvic organ prolapse as well as levator function and anatomy. It is at least equivalent to other imaging techniques in diagnosing, such diverse conditions as urethral diverticula, rectal intussusception and avulsion of the puborectalis muscle. Ultrasound is the only imaging method capable of visualizing modern slings and mesh implants and may help selecting patients for implant surgery. Delivery-related levator injury seems to be the most important etiological factor for pelvic organ prolapse and recurrence after prolapse surgery, and it is most conveniently diagnosed by pelvic floor ultrasound. This review gives an overview of the methodology. Its main current uses in clinical assessment and research will also be discussed.