Method for generating digitization breath gate-control signal based on abdomen body-surface skeleton line

Abstract

The invention relates to a method for generating digital respiratory gating signals based on an abdominal body surface outline, which comprises the following steps: (1) respectively extracting the abdominal body surface outline in each frame image of a reference abdominal video, and calculating normalized correlation coefficients NCC of the abdominal body surface outline at each moment and a reference outline to obtain an NCC-time curve; (2) arranging a grating window on the NCC-time curve, and providing a grating type label for the each frame image; (3) converting the each frame image of the reference abdominal video into a column vector to form a training set containing the type label; (4) reducing the dimension of the training set to obtain a support vector omega and a classification threshold value b by training; and (5) converting a real-time abdominal video into a column vector, and using the support vector omega and the classification threshold value b to calculate a sorting signal of each column vector to obtain sorting signals, namely, the gating signals. The method can lower cost, cannot bring uncomfortable feeling for a patient, and has good tolerance.

Description

technical field [0001] The invention relates to the field of digital automatic control, in particular to a method for generating a digital respiratory gating signal based on the contour of the abdomen body surface, which is applied to radiotherapy of thoracic and abdominal tumors. Background technique [0002] Respiratory exercise usually causes large-scale movement of thoracic and abdominal organs, which not only seriously affects the radiotherapy effect of thoracic and abdominal tumors, but also causes normal tissues to be irradiated and increases the chance of radiotherapy complications. At present, the commonly used method is to introduce respiratory gating technology to control the switch of the radiation beam, so that the working cycle of the radiation beam is synchronized with a specific breathing time, so that the residual movement of the tumor in the gating window is minimized. [0003] Current respiratory gating techniques are generally divided into the following t...

AI Technical Summary

Problems solved by technology

Its disadvantages are: (1) the body surface markers are prone to shift relative to the human body; (2) the infrared device is used, and the equipment is expensive, which is not conducive to the promotion of the respiratory gating system

The disadvantage of this technique is that the abdominal belt or deformation gauge causes a certain compression on the patient's abdomen, which brings discomfort to the patient and is poorly tolerated

[0007] The shortcomings of the above-mentioned several techniques prevent the widespread application of the respiratory gating technique, which limits the effect of radiotherapy for thoracic and abdominal tumors to a certain extent.

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