Impact of transducer position on B1+ homogeneity and RF safety in transcranial MR‐guided focused ultrasound: An electromagnetic simulation study

Abstract

Transcranial magnetic resonance‐guided focused ultrasound (tcMRgFUS) allows precise focal heating under magnetic resonance imaging (MRI) guidance for neurological therapies. However, large hemispherical transducers inherently affect the transmit radiofrequency (RF) field (|B1+|) inhomogeneity, producing dark/black‐band artifacts owing to general electromagnetic (EM) field interactions.