Olivier Beuf1, Franck Jaillon2, Mircea Armenean2, Herv Saint-Jalmes3, Frank Pilleul4
1Universit de Lyon, CREATIS-LRMN , CNRS UMR 5220; Inserm U630; INSA-Lyon; Universit Lyon 1, Villeurbanne, France; 2Universit de Lyon, CREATIS-LRMN, CNRS UMR 5220; Inserm U630; INSA-Lyon; Universit Lyon 1, Villeurbanne, France; 3LTSI, Inserm U642, Universit Rennes 1; Dpartement d'Imagerie, Centre Eugne Marquis, Rennes, France; 4Universit de Lyon, CREATIS-LRMN, CNRS UMR 5220; Inserm U630; INSA-Lyon; Universit Lyon 1; Hospice Civils de Lyon, Lyon, France
The imaging of the anal apparatus is important in the management of patients suffering from anorectal disease. A double loop coil prototype (10 mm outer diameter) was designed based on electromagnetic simulations. The angle between both loops was optimized to improve radial uniformity of the RF B1 field compared to a single loop. Minimum radial variation of signal intensity was found for an angle between 50 and 70. SNR measured at the close vicinity of the coil was 30 times higher than with the phased-array body coil used for abdominal clinical exams. Moreover, the SNR was superior to phased-array body coil up to about a radius of 30 mm from the coil centre. High-resolution magnetic resonance imaging acquired in the swine provided excellent visualizations of normal anal sphincter complex anatomy. The results are promising and suggest useful applications in the management of anorectal diseases with minimally invasive procedure.