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Updated: Jun 4, 2026

Quantification of Levator Ani Hiatus Enlargement by Magnetic Resonance Imaging in Males and Females with Pelvic Organ Prolapse
Published on: April 17, 2019
Visualization of pelvic floor reflex and voluntary contractions
Christos E Constantinou1, Daniel Korenblum, Bertha Chen
1Spinal Cord Injury Center, Palo Alto Veterans Administration, Palo Alto, CA 94305, USA. ceconst@stanford.edu
Abstract:
Visualization of the geometric deformation and associated displacement patterns of tubular abdominal organs to mechanical stimuli provides a quantitative measure that is useful in modeling their elastic properties. The origin of the stimulus may be the result of direct and voluntary muscle contraction or in response to a triggered reflex activity. Using trans-perineal 2D ultrasound imaging we examined the characteristics of deformation and displacement of these organs in response to voluntary activity, contraction, straining, and fast reflex responses to stimuli such as coughing. The relative time sequence in movement was examined by serially segmenting the outline of these structures and mapping their temporal characteristics.
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