Magnetic resonance guided hyperthermia

Apparatus for hyperthermia treatment, comprising:

• an MRI machine having an MR imaging resonant frequency for generating an MR image of a patient;
• means including an RF phased array including a plurality of individually adjustable antenna elements positioned within the MRI machine for directing RF radiation having a frequency substantially equal to the resonant frequency at a tumor within the patient situated within the MRI machine;
• means for supplying a temporally averaged energy distribution to said patient to improve localization of the tumor during a hyperthermia treatment;
• and
• means for determining and forming a visual display of an specific absorption ratio (SAR) distribution of radiation emitted by said antenna elements prior to the hyperthermia treatment for comparison with the MR image of the patient in order to predict adjustments of the antenna elements which will provide for optimum coverage of the tumor and thereby predict said temporally averaged energy distribution during the hyperthermia treatment.

Apparatus for hyperthermia treatment, comprising:

• an MRI machine having an MR imaging resonant frequency for generating an MR image of a patient;
• means including an RF phased array including a plurality of individually adjustable antenna elements positioned within the MRI machine for directing RF radiation having a frequency substantially equal to the resonant frequency at a tumor within the patient situated within the MRI machine;
• and
• means for determining and forming a visual display of an specific absorption ratio (SAR) distribution of radiation emitted by said antenna elements for comparison with the MR image of the patient in order to predict adjustments of the antenna elements which will provide for maximum coverage of the tumor during a subsequent hyperthermia treatment, said SAR distribution being obtained by measuring current distributions resulting from emission of said radiation by said antenna elements prior to the treatment.

A method of treatment, comprising the steps of:

• placing a patient in a MRI machine including bolus/treatment array and taking a conventional MRI image;
• using an RF phased array in said bolus/treatment array to generate a specific absorption ratio (SAR) map image to permit obtaining appropriate phase, amplitude, and temporal averaging;
• and
• superimposing the conventional and SAR map images and adjusting the phase and amplitude settings if necessary to obtain congruence between the images;
• and subsequently applying RF radiation from the phased array to heat the tumor.

A method of hyperthermia treatment, comprising the steps of:

• placing a patient in a bolus/treatment array situated in an MRI machine;
• applying RF energy to the patient and measuring resulting current densities in order to generate an specific absorption ratio (SAR) map of the patient;
• using the SAR map as a basis for temporally averaging radiation to be applied to the patient during a hyperthermia treatment;
• and
• providing the hyperthermia treatment by applying the temporally averaged RF radiation to the patient in order to heat a tumor in the patient to a predetermined temperature for a predetermined period of time.