Alessandro Digesu

Prevalence of pubovisceral muscle avulsion in a general gynecology cohort: A computed tomography (CT) study

To calculate the prevalence of pubovisceral muscle (PM) avulsion in a cohort of women presenting at a university hospital for non‐urogynecological conditions.

Real-time in vivo assessment of levator ani muscle deformation in women

OBJECTIVE To study the deformation of the levator ani muscle in vivo with the use of real-time ultrasound imaging of the pelvic floor. STUDY DESIGN Thirty-two women with symptoms of pelvic floor dysfunction underwent real-time in vivo assessment of the strain of the pelvic floor during Valsalva effort. All participants underwent clinical examination, urodynamics and 3D/4D translabial ultrasound scan of the pelvic floor. The deformation curves of the levator ani muscle were plotted and the difference in compliance according to the grade of urogenital prolapse was measured. One-way ANOVA and Spearmans correlation were used to test for significance of the relationship between variables (significance level P<0.05). Test-retest analysis of the ultrasound measurements of the levator hiatal dimensions was also conducted using intra-class correlation coefficient (ICC). RESULTS The deformation curve of the levator hiatus showed a non-linear relationship with gradually increased Valsalva force, which was quite pronounced in the pubourethralis subdivision of the levator ani muscle complex. Women with significant pelvic organ prolapse demonstrated a less compliant levator ani muscle close to its origin from the pubic bone than women with non-significant prolapse (median maximum strain 26% vs 32%, respectively, P=0.03). CONCLUSIONS Real-time in vivo assessment of levator ani muscle deformation in women is feasible and yields significant information.

Authors' response re: Shek KL & Dietz H. Letter to the Editor Re: 'Do ultrasound findings of levator ani "Avulsion" correlate with anatomical findings: A multicenter cadaveric study'.

Dear Editor We thank Ka Lai Shek and Hans Peter Dietz for their comments and the opportunity to clarify some of the points raised. The methodology used to image the cadavers was that quoted in in Dietz HP, Bernardo M, Kirby A, et al. Minimal criteria for the diagnosis of avulsion of the puborectalis muscle by tomographic ultrasound. Int Urogynecol J. 2010; 22: 699– 704. An ‘‘avulsion’’ injury was confirmed if discontinuity was identified between the PVM and the pelvic sidewall in at least three slices not two as incorrectly transcribed in the manuscript. Shek and Dietz, have suggested that imaging, whether by ultrasound or MRI, is virtually impossible in cadavers. We disagree with this statement. Cadavers produce morphological findings generally transferable to the living subject and there are hundreds of studies that have used cadavers as a medium for assessing imaging findings. Moreover, musculoskeletal studies have found that the size of a tear increases with time in cadaveric studies, supporting the argument that if an ‘‘avulsion’’ was the literal detachment of the PVM from its insertion, as a consequence of traumatic vaginal delivery, this should be observed in the cadaveric specimen. Nonetheless, the aim of this study is not to directly investigate the clinical significance of the ‘‘avulsion’’ but rather to determine whether the finding on ultrasound imaging of an ‘‘avulsion’’ is an anatomical detachment of PVM from its insertion. Our study has found this not to be the case and it is a misnomer. In addition, Shek and Dietz, queried the methodology related to the identification of an ‘‘avulsion’’ on dissection, suggesting that the researchers in our study were unable to show agreement. This is an incorrect statement. There was 100% (perfect) agreement for the presence or absence of an anatomical ‘‘avulsion’’. In fact, there was not a single ultrasonographically observed ‘‘avulsion’’ seen on anatomical dissection. In this paper we have found that ‘‘avulsions’’ are associated with a narrowing of the PVM attachment depth. This may be the anatomical finding which is visible on MRI , in delivery suite , in the operating theatre and on clinical examination. We have proposed some explanations for this altered imaging finding such as the ‘‘avulsion’’ representing the early decent of the anterior compartment or that there is a change in the tissue composition. These hypotheses are yet to be proven but we hope this study will equip researchers throughout the world to look for an answer to these questions. With kind regards,