Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Jul;34(7):1627-1633.
doi: 10.1007/s00192-022-05441-w. Epub 2023 Jan 19.

Multimodal measurements of levator bowl volume in nulligravid asymptomatic women: endovaginal ultrasound versus MRI

Henry H Chill #  1 , Liam C Martin #  2 , Steven D Abramowitch  2 , Ghazaleh Rostaminia  3
Affiliations

Multimodal measurements of levator bowl volume in nulligravid asymptomatic women: endovaginal ultrasound versus MRI

Henry H Chill et al. Int Urogynecol J. 2023 Jul.

Abstract

Introduction and hypothesis: Measurements of levator bowl volume using advanced imaging, may be predictive of pelvic floor muscle function. The aim of this study was to compare the volume of the levator bowl using both magnetic resonance imaging (MRI) and endovaginal ultrasound (EVU) of healthy asymptomatic women.

Methods: All participants underwent a comprehensive interview including completion of the Pelvic Floor Distress Inventory Questionnaire-20 questionnaire, pelvic examination with a pelvic organ prolapse quantification evaluation, MRI, and EVU. The pelvic floor was segmented using Slicer and the MRI segmentations were trimmed using two methods: soft-tissue landmarks and the field of view (FOV) of the ultrasound volume. The levator bowl volume of the 3D segmented shapes was measured using Blender's 3D printing toolkit. Normality was tested using the Shapiro-Wilks test and comparisons were made using self-paired t tests.

Results: The final analysis included 19 patients. Levator bowl volume measured via MRI was larger than that measured in EVU (46.1 ± 7.9 cm3 vs 27.4 ± 5.9 cm3, p<0.001). Reducing the FOV of the MRI to that of EVU caused the MRI volume to be much closer to the EVU volume (35.5 ± 3.3 cm3 vs 27.4 ± 5.9 cm3, p<0.001); however, it remained significantly larger.

Conclusion: Levator bowl volume measured using MRI was larger than that measured using EVU no matter the method of delineation of the levator muscles. Although EVU is safe, cheap, and easy to perform, it captures a smaller volume of levator bowel than MRI.

Keywords: Endovaginal ultrasound; Levator ani muscle; Levator bowl volume; Magnetic resonance imaging; Pelvic organ prolapse.

PubMed Disclaimer

References

    1. Wu JM, Vaughan CP, Goode PS, et al. Prevalence and trends of symptomatic pelvic floor disorders in U.S. women. Obstet Gynecol. 2014;123(1):141–8. - DOI - PubMed - PMC
    1. Ramaseshan AS, Felton J, Roque D, Rao G, Shipper AG, Sanses TVD. Pelvic floor disorders in women with gynecologic malignancies: a systematic review. Int Urogynecol J. 2018;29(4):459–76. - PubMed
    1. DeLancey JOL, Kearney R, Chou Q, Speights S, Binno S. The appearance of levator ani muscle abnormalities in magnetic resonance images after vaginal delivery. Obstet Gynecol. 2003;101(1):46–53. https://doi.org/10.1016/S0029-7844(02)02465-1 . - DOI - PubMed - PMC
    1. Dietz HP, Lanzarone V. Levator trauma after vaginal delivery. Obstet Gynecol. 2005;106(4):707–12. - DOI - PubMed
    1. Dietz H, Simpson J. Levator trauma is associated with pelvic organ prolapse. BJOG. 2008;115(8):979–84. - DOI - PubMed

LinkOut - more resources