Hadron radiation installation and verification method

A method for performing a proton radiation therapy verification session using a proton radiation installation comprising:

• a target support configured to support a target;
• a proton radiation apparatus adapted to emit a proton radiation beam along a beam axis to irradiate the target supported by the target support, said radiation beam penetrating into the target,
• wherein the radiation apparatus has a control system at least comprising a beam penetration depth control allowing at least to control and vary the penetration depth of the radiation beam into the target,
• a radiation beam range sensor device adapted to determine the penetration depth of said radiation beam into the target, wherein said range sensor device comprises a gamma camera responsive to prompt gamma rays that are emitted while said radiation beam penetrates into the target,
• said gamma camera comprising:
• a collimator having a wall that blocks gamma radiation and an aperture in said wall,
• a detector comprising one or more scintillation elements upon which gamma radiation passing through said aperture of the collimator is incident, and
• an electronic readout mechanism associated with said detector,
• wherein the collimator of the gamma camera is a slit collimator having an elongated slit aperture,
• wherein the collimator is a variable width slit collimator having an elongated slit aperture of variable width, said collimator comprising a first collimator member and a second collimator member that each define one of the opposed longitudinal edges of the slit aperture, said collimator having a slit width actuator mechanism for displacing and positioning said first and second collimator members relative to one another,
• wherein the slit width actuator mechanism is linked to the control system,
• wherein the method for performing the proton radiation therapy verification session comprises:
• arranging a phantom on the target support,
• operating the proton radiation apparatus to emit a proton radiation beam along the beam axis to irradiate the phantom supported by the target support, said radiation beam penetrating into the phantom, and
• determining with the radiation beam range sensor device an actual penetration depth of said radiation beam into the phantom;
• wherein the control system is adapted to input and store in a memory thereof one or more sets of radiation session control data corresponding to one or more radiation sessions to be performed with the proton radiation apparatus,
• wherein the method for performing the proton radiation therapy verification session comprises:
• arranging a phantom on the target support,
• storing in the memory data representing a pattern of varying beam penetration depth during the proton radiation therapy verification session,
• storing in the memory data representing a pattern of variation of the slit width of the collimator to be performed by the slit width actuator mechanism in synchronicity with the varying beam penetration depth pattern during the proton radiation therapy verification session,
• operating the proton radiation apparatus and emitting a proton radiation beam along the beam axis to irradiate the phantom supported by the target support, said radiation beam penetrating into the phantom with said varying beam penetration depth, and
• operating the slit width actuator mechanism in synchronicity with the varying beam penetration depth pattern during the proton radiation therapy verification session.