Anti-collision control method for leaves of multileaf collimator

Abstract

The invention relates to an anti-collision control method for leaves of a multileaf collimator. The anti-collision control method for the leaves of the multileaf collimator includes the following steps that in static intensity modulated radiotherapy, the difference between the real-time positions and the target positions to which the leaves move is compared with the difference between the initial positions of the leaves and the target positions to which the leaves move to keep adjusting the operating speed of a motor for driving the leaves to move; the closer the real-time positions of the leaves are to the target positions, the lower the operating speed of the motor is, and then collision between the leaves caused when the two sets of leaves are closed can be effectively prevented; in dynamic intensity modulated radiotherapy, when whether the motor moves forward or backward is judged, the number of pulses emitted by an actual motor position coder and measured by the i sub-field in real time is compared with the upper limit value SlidePosH and the lower limit value SlidePosL to judge whether the motor brakes or keeps sliding forward due to inertia or keeps running at a certain speed of Vo[i]. Thus, the position actually reached by the motor in the operating process is basically identical to the target position, it is guaranteed that the error of the position is within + / -e, faults such as mechanical damage caused by leaf collision are prevented, and the end faces of the leaves are prevented from leaking rays.

Description

technical field [0001] The invention relates to the technical field of medical electronics, in particular to a blade control method of a multi-leaf collimator. Background technique [0002] The multi-leaf collimator is an advanced stereotactic radiosurgery medical device, which can cooperate with a linear accelerator or a cobalt-60 machine to perform conformal intensity-modulated treatment of tumors, so as to improve the gain ratio of radiotherapy (that is, to maximize the intensity of the radiation The purpose is to concentrate the dose into the lesion, kill tumor cells, and make the surrounding normal tissues and organs receive less or avoid unnecessary irradiation). It is one of the main devices for tumor treatment today. It replaces the traditional lead baffles with several pairs of high-density tungsten alloy blades arranged in opposite directions in A and B groups to shield the rays, drives the blades and blade groups with corresponding logarithmic motors, and detects...

AI Technical Summary

Problems solved by technology

In order to avoid failures such as mechanical damage caused by the relative collision of paired blades, the current main method is to leave a small gap, but this method increases the leakage rays of the end faces of the blades that are not completely closed, which is harmful to the human body

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