Medical apparatus with a radiation therapy device and a radiation detection system

A computer program product stored in a non-transitory computer readable medium comprising machine executable instructions for execution by a processor controlling a medical apparatus, wherein the medical apparatus comprises a magnetic resonance imaging system for acquiring magnetic resonance data from a subject within an imaging zone, wherein the magnetic resonance imaging system comprises a main magnet for generating a magnetic field with a main field region, wherein the imaging zone is within the main field region, wherein the medical apparatus further comprises a radiation therapy device comprising a gantry and a radiation source, wherein the gantry is operable for rotating the radiation source about a rotational axis, wherein the radiation source is operable for generating a radiation beam directed at the rotational axis, wherein the radiation source is operable for directing the radiation beam towards a target volume, wherein the rotational axis intersects the target volume, wherein the target volume is within the imaging zone, wherein the medical apparatus further comprises a radiation detection system covering a substantial part of the rotation of the gantry and operable for measuring radiation detection data descriptive of the path and intensity of the radiation beam at the intersection of the radiation beam with at least one surface surrounding the subject using at least one radiation detector, wherein the at least one radiation detector is operable for being placed within the main field region, wherein the medical apparatus further comprises a subject support operable for supporting the subject, wherein execution of the instructions cause the processor to:

• receive a treatment plan descriptive of the irradiation of a target zone within the subject, wherein the subject support is further operable for positioning the target volume within the target zone;
• acquire the magnetic resonance data from the imaging zone using the magnetic resonance imaging system;
• generate radiation therapy device control commands using the magnetic resonance data and the treatment plan;
• irradiate the target zone by controlling the radiation therapy device using the radiation therapy device control commands;
• measure the radiation detection data during irradiation of the target zone using the radiation detection system;
• and
• determine a time dependent radiation beam path and a time dependent radiation beam intensity using the radiation detection data, wherein the time dependent radiation beam path is descriptive of the path of the radiation beam through the subject as a function of time, wherein the time dependent radiation beam intensity is descriptive of the intensity of the radiation beam in the subject as a function of time.

A method of operating a medical apparatus, wherein the medical apparatus comprises a magnetic resonance imaging system for acquiring magnetic resonance data from a subject within an imaging zone, wherein the magnetic resonance imaging system comprises a main magnet for generating a magnetic field with a main field region, wherein the imaging zone is within the main field region, wherein the medical apparatus further comprises a radiation therapy device comprising a gantry and a radiation source, wherein the gantry is operable for rotating the radiation source about a rotational axis, wherein the radiation source is operable for generating a radiation beam directed at the rotational axis, wherein the radiation source is operable for directing the radiation beam towards a target volume, wherein the rotational axis intersects the target volume, wherein the target volume is within the imaging zone, wherein the medical apparatus further comprises a radiation detection system covering a substantial part of the rotation of the gantry and operable for measuring radiation detection data descriptive of the path and intensity of the radiation beam at the intersection of the radiation beam with at least one surface surrounding the subject using at least one radiation detector, wherein the at least one radiation detector is operable for being placed within the main field region, wherein the medical apparatus further comprises a subject support operable for supporting the subject, wherein the method comprises the steps of:

• receiving a treatment plan descriptive of the irradiation of a target zone within the subject, wherein the subject support is further operable for positioning the target volume within the target zone;
• acquiring the magnetic resonance data from the imaging zone using the magnetic resonance imaging system;
• generating radiation therapy device control commands using the magnetic resonance data and the treatment plan;
• controlling the radiation therapy device using the radiation therapy device control commands for irradiating the target zone;
• measuring the radiation detection data during irradiation of the target zone using the radiation detection system;
• and
• determining a time dependent radiation beam path and a time dependent radiation beam intensity using the radiation detection data, wherein the time dependent radiation beam path is descriptive of the path of the radiation beam through the subject as a function of time, wherein the time dependent radiation beam intensity is descriptive of the intensity of the radiation beam in the subject as a function of time.