OBJECTIVE: The purpose of this study was to determine the shape and characteristics of the vaginal high-pressure zone (HPZ) by imaging a compliant fluid-filled bag that had been placed in the vaginal HPZ with the 3-dimensional ultrasound system. STUDY DESIGN: Nine nulliparous asymptomatic women underwent 3-dimensional ultrasound imaging and vaginal pressure measurements. A compliant bag was placed in the vagina and filled with various volumes of water. Three-dimensional ultrasound volumes of the pelvic floor were obtained at each bag volume while the subjects were at rest and during pelvic floor contraction. RESULTS: At low volumes, the bag was collapsed for a longitudinal extent of approximately 3.3 +/- 0.2 cm (length of vaginal HPZ). With increasing bag volume, there was opening of the vaginal HPZ in the lateral dimension before the anteroposterior dimension. Pelvic floor contraction produced a decrease in the anteroposterior dimension but not the lateral dimension of the bag in the region of the vaginal HPZ. CONCLUSION: We propose that the shape and characteristics of the vaginal HPZ are consistent with the hypothesis that the puborectalis muscle is responsible for the genesis of the vaginal HPZ.
OBJECTIVE: The purpose of this study was to determine the shape and characteristics of the vaginal high-pressure zone (HPZ) by imaging a compliant fluid-filled bag that had been placed in the vaginal HPZ with the 3-dimensional ultrasound system. STUDY DESIGN: Nine nulliparous asymptomatic women underwent 3-dimensional ultrasound imaging and vaginal pressure measurements. A compliant bag was placed in the vagina and filled with various volumes of water. Three-dimensional ultrasound volumes of the pelvic floor were obtained at each bag volume while the subjects were at rest and during pelvic floor contraction. RESULTS: At low volumes, the bag was collapsed for a longitudinal extent of approximately 3.3 +/- 0.2 cm (length of vaginal HPZ). With increasing bag volume, there was opening of the vaginal HPZ in the lateral dimension before the anteroposterior dimension. Pelvic floor contraction produced a decrease in the anteroposterior dimension but not the lateral dimension of the bag in the region of the vaginal HPZ. CONCLUSION: We propose that the shape and characteristics of the vaginal HPZ are consistent with the hypothesis that the puborectalis muscle is responsible for the genesis of the vaginal HPZ.
Authors: Milena M Weinstein; Dolores H Pretorius; Sung-Ae Jung; Jennifer J Wan; Charles W Nager; Ravinder K Mittal Journal: Int Urogynecol J Date: 2011-05-21 Impact factor: 2.894
Authors: Louise T S Arenholt; Bodil Ginnerup Pedersen; Karin Glavind; Marianne Glavind-Kristensen; John O L DeLancey Journal: Int Urogynecol J Date: 2016-09-17 Impact factor: 2.894
Authors: Ali Zifan; Ravinder K Mittal; David C Kunkel; Jessica Swartz; Garrett Barr; Lori J Tuttle Journal: Am J Physiol Gastrointest Liver Physiol Date: 2019-11-18 Impact factor: 4.052
Authors: Milena M Weinstein; Dolores H Pretorius; Sung-Ai Jung; Charles W Nager; Ravinder K Mittal Journal: Clin Gastroenterol Hepatol Date: 2008-08-16 Impact factor: 11.382