The Earlier Study Of Two-dimensional And Three-dimensional Ultrasonography In Levator Trauma After Vaginal Delivery

ObjectiveThis study was designed to establish standard two-dimensional section and measurementmethod for observing puborectalis muscle, and to obtain the normal the thickness and thickingrate of puborectalis muscle, to observe the ultrasound performance characteristics of levator aniof postpartum female by vaginal delivery for discussing the correlation of levator trauma andfirst vaginal delivery by combining using of two-dimensional and three-dimensional ultrasoundfor the diagnosis of ultrasound evaluation the levator trauma in the early stage.MethodsChosen120postpartum prolapse female by first vaginal delivery as research group,and78normal young nulliprarous were chosen as control group.All were examined by two-dimensionaland three-dimensional ultrasound at rest and on the contract.On the two-dimensional scanning,all were measured on pelvic floor parasagittal plane at three levels--urethral level (anterior),vaginal level (central) and rectal level (posterior), both at rest and contraction. Tomographicultrasound imaging was performed on volumes obtained at maximal pelvic floor contraction at2.5mm slice intervals, from5mm below to12.5mm above the plane of minimal hiataldimensions, producing eight slices per patient,and observat levator hiatus and levator ani.biometric indices of levator hiatus were measured. And we compared the thickening rate ofanterior part of puborectalis muscle with each biometry with research group and control group.Results(1)The normal young nulliprarous can get a clear two-dimensional oblique parasagittalsection,which can display clearly the transverse section of the pubic descending, the osseouscortex echo and the lengthy levator ani which perpendicular pubic ramus.(2) At rest, thickness of anterior part:Left（9.23±0.20）mm,Right（8.99±0.20）mm；Central:Lef（t10.37±0.24）mm,Righ（t10.05±0.22）mm；Posterior：Lef（t8.00±0.16）mm,Righ（t8.07±0.15）mm. At contraction, thickness of anterior parts of bilateral puborectalis muscle were significantly thicker than central or posterior parts (p<0.05). The interclass coefficients were more than0.93and0.83.(3) On the two-dimensional image, thickness of bilateral puborectalis muscle haven’tsignificant difference between the normal young nulliprarous and postpartum prolapse group atrest,but with significant difference on the contract.(4) On the theree-dimensional image, biometric indices of levator hiatus between the normalyoung nulliprarous and postpartum prolapse group have significant difference both at rest andcontract except levator ani width,which has significant difference on the contract but not at rest.Conclusions(1)The endoluminal two dimensional ultrasonography can be used to dynamically observepuborectalis muscle morphologies and contractile function of puborectalis on pelvic floorparasagittal plane. It is simple, reproducible and worthy of clinical promotion.(2) The thickness and thicking rate of puborectalis muscle of the postpartum prolapse groupare obviously descend on the contract, which explained. There have correlation between vaginaldelivery and levator ani stress.(3)The biometric indices of levator hiatus of the postpartum prolapse group are smaller thannormal both at rest and contract. It explained the levator anicontraction strength of pelvic organprolapse haven descended and proved vaginal delivery was a risk factors for levator ani trauma.