Charged particle cancer therapy and patient breath monitoring method and apparatus
View Patent ↗The invention comprises a patient respiration monitoring and/or control method and apparatus used in conjunction with multi-axis charged particle or proton beam radiation therapy of cancerous tumors. The respiration monitoring system uses thermal and/or force sensors to determine where a patient is in a respiration cycle in combination with a feedback signal control delivered to the patient to inform the patient when breath control is required. The resulting breath control is timed with charged particle delivery to the tumor to enhance accuracy, precision, and/or efficiency of tumor treatment.
1. An apparatus for controlling extraction of charged particles from a synchrotron for irradiation therapy of a tumor of a patient, comprising:
a synchrotron configured to accelerate the charged particles, said synchrotron comprising:
a radio-frequency cavity system comprising a first pair of blades for inducing oscillation of the charged particles; and
a foil configured to yield slowed charged particles from the charged particles having sufficient oscillation to traverse said foil, wherein the slowed charged particles pass through a second pair of blades having an extraction voltage directing the charged particles out of said synchrotron through a Lamberson extraction magnet, said radio-frequency cavity system for inducing oscillation configured and timed using said respiration signal;
a respiration sensor generating a respiration signal, said respiration signal corresponding to a variable rate breathing pattern of the patient, said respiration sensor comprising at least one of:
a force meter strapped to the patient's chest;
a first thermal resistor configured in a first position proximate an exhalation path of the patient; and
a second thermal resistor configured in a second position both out of the exhalation path of the patient and in a local room environment common with the patient, wherein said respiration signal is generated using differences between readings from said first thermal resistor and said second thermal resistor,
wherein said radio-frequency cavity system for inducing oscillation is timed using said respiration signal to time extraction of the charged particles to the tumor based on said variable rate breathing pattern.
2. The apparatus of claim 1 , further comprising:
a charged particle controller controlling delivery of the charged particles from the synchrotron at sequential non-periodic intervals, said non-periodic intervals correlating with said variable rate breathing pattern, wherein said breathing pattern comprises sequential respiration cycles varying by at least one second in length.
3. The apparatus of claim 1 , further comprising:
an X-ray generation source configured to generate X-rays of the patient and the tumor at said non-periodic intervals.