Functional magnetic resonance imaging of the pelvic floor: Dynamic pressure and morphological changes in the levator ani muscle on straining demonstrated by MR-assisted biomechanical modelling - Tan,E; Lee,S-L; Gedroyc,W; Cornish,JA; Darzi,A; Yang,G-Z; Khullar,V; Tekkis,PP (GASTROENTEROLOGY, 2008)