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Abstract #2920

MR ARFI Using the Keyhole Technique: Acceleration of MR-Guided Adaptive Focusing for Transcranial Ultrasonic Brain Therapy

Raphal Paquin1, 2, Alexandre Vignaud3, Laurent Marsac4, 5, Youliana Younan4, Stphane Lehricy1, 6, Mickal Tanter4, Jean-Franois Aubry4

1CENIR - Centre de NeuroImagerie de Recherche, ICM - Institut du Cerveau et de la Moelle pinire, Paris, France; 2CRICM, Universit Pierre et Marie Curie (Paris 6)/INSERM UMR_S975/CNRS UMR 7225, Paris, France; 3Siemens Healthcare, F-93527 St Denis 2, France; 4Institut Langevin, ESPCI ParisTech, CNRS UMR 7587, INSERM U979, Paris, France; 5SuperSonic Imagine, Aix en Provence, France; 6Groupe Hospitalier Piti-Salptrire, Paris, France

Magnetic resonance acoustic radiation force imaging (MR ARFI) provides a quantitative measurement of tissue displacement induced by the acoustic radiation force. Adaptive focusing of transcranial HIFU beams requires a large number of MR ARFI images and thus calls for fast imaging techniques. This work proposes to combine a two-dimensional spin-warp MR ARFI pulse sequence with the keyhole technique. Our approach offers a compromise between spatial resolution, SNR, acquisition speed, minimal heat deposition, accurate localization of the focal spot, and could be valuable for adaptive focusing procedures.

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Keywords

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