Thermal monitoring of tissue during a thermal therapy may include identifying an imaging plane bisection axis lying along at least one of a longitudinal axis of a thermal therapy instrument and a vector through a region of interest. The method may include identifying multiple thermal monitoring planes used in monitoring thermal therapy of the volume, where each thermal monitoring plane intersects the region of interest, where a first thermal monitoring plane intersects a second thermal monitoring plane at the imaging plane bisection axis, and the first thermal monitoring plane is offset from the second thermal monitoring plane by an angle of intersection. The method may include and performing thermal monitoring of the thermal therapy by obtaining magnetic resonance (MR) images obtained from the first monitoring plane and the second monitoring plane, and calculating, based on the images, temperature data of the volume.