BACKGROUND: Pelvic organ prolapse (POP) is a condition characterized by the failure of various anatomic structures to support the pelvic viscera. There has been a growing interest in the understanding of the underlying structural alterations in the pelvic floor, and the use of 2D and 3D transperineal ultrasound has recently been shown to be able to determine biometric indices of the levator hiatus and pubovisceral muscle.
OBJECTIVE: To compare the morphological features and biometric parameters of the pelvic floor of patients with pelvic organ prolapse with age-matched controls using 2D and 3D transperineal ultrasound.
METHODOLOGY: In a prospective case control study, 35 patients with prolapse and 25 asymptomatic controls were assessed. Bladder symphyseal distance (BSD), bladder neck descent, angle of urethral inclination, retrovesical angle, bladder wall thickness and quantification of prolapse were measured on rest and valsalva maneuver on 2D ultrasound. Anteroposterior and lateral diameters, as well as pubovisceral muscle thickness was measured on rest and valsalva on 3D ultrasound.
RESULTS: BSD was significantly lower in the prolapse group (p=0001), while bladder wall thickness was significantly higher (p=0024). AP and lateral diameters were significantly higher in the prolapse group both at rest and on valsalva, showing that there is significant correlation with increased diameters at rest and pelvic organ descent. Pubovisceral muscle thickness was lower in the prolapse group compared to controls both at rest and on valsalva.
CONCLUSION: Levator hiatal dimensions and biometry indices of the pubovisceral muscle can be determined using 2D and 3D transperineal ultrasound. There is significant correlation between anteroposterior and lateral diameters, as well as pubovisceral thickness, with pelvic organ descent.