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Abstract #0406

Magnetic Resonance Elastography of the Anal Sphincter

Scott A. Kruse1, David S. Lake2, Armando Manduca, 12, Phillip J. Rossman1, Jessica R. Edge3, Joel G. Fletcher1, Joel P. Felmlee1, Richard L. Ehman1, Adil E. Bharucha3

1Radiology, Mayo Clinic, Rochester, MN, United States; 2Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN, United States; 3Clinical and Enteric Neuroscience Translational and Epidemiological Research Program (C.E.N.T.E.R.), Mayo Clinic, Rochester, MN, United States

The relationship between imaging findings and function of the anal sphincter in fecal incontinence is not well understood. Anal sphincter stiffness has not been assessed by any technique, including magnetic resonance elastography (MRE), in humans. We performed MRE exams on six patients at 120 Hz with a customized driver and an endorectal coil. The median shear stiffness value of the internal sphincter for all patients was 3.7 kPa. Although further work is necessary to assess reproducibility and establish normal stiffness values and their variation with disease, it is possible to quantify anal sphincter stiffness with MRE.

Keywords

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