Medical instrument for external beam radiotherapy and brachytherapy

A computer readable storage medium storing machine executable instructions for execution by a processor for controlling a medical instrument, wherein the medical instrument comprises a magnetic resonance imaging system for acquiring magnetic resonance data from a subject within an imaging zone, wherein the medical instrument further comprises an external beam radiotherapy system for irradiating a target zone with a beam of ionizing radiation within the imaging zone, wherein execution of the instructions cause the processor to:

• acquire magnetic resonance data from the subject using the magnetic resonance imaging system;
• reconstruct a magnetic resonance image from the magnetic resonance data;
• receive planning data, wherein the planning data specifies a spatially dependent radiation dose for the target zone;
• register the planning data to the magnetic resonance image;
• and
• calculate an external beam dosage plan and a brachytherapy dosage plan using the spatially dependent radiation dose and the magnetic resonance image and where
• the external beam dosage plan is a plan or commands for irradiating the target zone using the external beam radiotherapy system and
• the brachytherapy dosage plan is a plan for irradiating the target zone using brachytherapy, the brachytherapy dosage plan including placement position of radioactive source(s) mounted on one or more catheters and time duration the radioactive source will remain at these position(s) and
• the computer readable medium further stores a catheter attenuation model descriptive of the attenuation of ionizing radiation by the one or more catheters, and wherein execution of the instructions causes the processor to calculate the external beam dosage plan at least partially using the catheter attenuation model.

A method of radiation therapy using a medical instrument and a brachytherapy catheter system, wherein the medical instrument comprises a magnetic resonance imaging system for acquiring magnetic resonance data from a subject within an imaging zone, wherein the medical instrument comprises an external beam radiotherapy system for irradiating a target zone with a beam of ionizing radiation within the imaging zone, wherein the brachytherapy catheter system comprises a brachytherapy catheter, wherein the method comprises:

• acquiring magnetic resonance data from the subject using the magnetic resonance imaging system;
• reconstructing a magnetic resonance image from the magnetic resonance data;
• receiving planning data, wherein the planning data specifies a spatially dependent radiation dose for the target zone;
• registering the planning data to the magnetic resonance image;
• calculating an external beam dosage plan and a brachytherapy dosage plan using the spatially dependent radiation dose and the magnetic resonance image;
• irradiating the target zone using the external beam radiotherapy system in accordance with the external beam dosage plan;
• monitoring insertion of the brachytherapy catheter in real time using the magnetic resonance imaging system, wherein a final placement of the brachytherapy catheter is determined using the magnetic resonance image and the brachytherapy dosage plan;
• controlling the insertion of a radioactive source into the brachytherapy catheter using the brachytherapy dosage plan and where
• the external beam dosage plan is a plan or commands for irradiating the target zone using the external beam radiotherapy system and
• the brachytherapy dosage plan is a plan for irradiating the target zone using brachytherapy, the brachytherapy dosage plan including placement position of radioactive source(s) mounted on (a) brachytherapy-catheter(s) and time duration the radioactive source will remain at these position(s) and
• the brachytherapy catheter is inserted prior to irradiating the target zone.