JP4247533B2 - Respiratory synchronizer - Google Patents

Description

  The present invention relates to a respiratory synchronization device.

  In radiation therapy for trunk organs such as the lungs and liver, the affected area moves due to the influence of breathing, so it is difficult to focus the beam only on the affected area without causing unnecessary exposure to normal tissue. There is a problem that it is. Similarly, in the radiation (for example) image diagnosis for the trunk, the target area moves due to the influence of respiration, and therefore there is a problem that the image quality of the captured image is deteriorated when breath holding is not performed. In both radiotherapy and diagnostic imaging, if beam irradiation or imaging is performed in synchronization with the end of expiratory phase (respiration bottom), where the movement of the organ is stopped for a relatively long time, It is said that the problem can be solved.

  Therefore, conventionally, a so-called respiration synchronization method has been adopted in which respiration signals are detected by various sensors and beam irradiation and image capturing are performed in synchronization with respiration. In this respiratory synchronization method, it is required that the patient's breathing is stable in order to perform treatment with a balance between irradiation efficiency and irradiation accuracy. (The respiratory synchronization method will be described in detail later.)

  In the invention according to Patent Document 1 (Japanese Patent Laid-Open No. 1-97445), which uses a respiratory synchronization method and is directed to a nuclear magnetic resonance apparatus, by letting a patient listen to music having a constant rhythm (tempo), breathing is performed at a constant cycle. After confirming that the steady state has been reached, photographing is started in synchronization with breathing. Furthermore, the invention of Patent Document 1 applies a so-called pull-in phenomenon in which a patient's breathing cycle is pulled into a bar period of music or an integer multiple of that, which is particularly called forced pull-in. It is. In the medical field, there are many cases where the patient's breathing is unstable, and it can be said that it is not sufficient to stabilize the breathing only by letting the patient listen to music with a certain rhythm.

  Further, Patent Document 1 describes a method of causing a patient to perform a regular operation such as turning an object having a constant moment of inertia. However, the use thereof leads to body movement of the trunk, and radiation. It cannot be said that it is suitable for treatment and diagnostic imaging.

  In the invention according to Patent Document 2 for a radiotherapy device, a gating method different from a normal respiratory synchronization method is proposed. That is, the respiratory cycle is predicted by pattern matching, and gating based on the respiratory phase obtained from the predicted respiratory cycle is performed. Prior to the predicted beam irradiation period, the gating system is started in advance to compensate for the mechanical rise time of the gating system, so that the ON state of the gate signal and the actual beam irradiation period are completely matched. Thereby, it is assumed that efficient beam irradiation is realized. By the way, human physiological behavior changes from moment to moment, and is greatly affected by minor changes in psychological state. Under such circumstances, prediction based on the pattern matching is insufficient. There is a big limit especially in exception handling. In other words, the ratio of physiological behavior that can be patterned under conditions where breathing is not stable is not large in all data. For this reason, the accuracy of prediction is deteriorated, the appearance frequency of the ON state of the gate signal is remarkably lowered, and the treatment time is greatly extended.

  As described above, the prediction of the respiratory cycle under the natural breathing state and the beam irradiation control at the predicted timing are effectively impossible, and cannot be applied to the actual treatment.

The invention of Patent Document 2 is a form that is unilaterally adapted to a human from a machine, and Patent Document 1 is a form that is unilaterally adapted to a machine. In any form, the feature is that the working relationship is unidirectional, and as long as it stays in such a form, it is considered that the above problems cannot be overcome.
JP-A-1-97445 Special table 2002-528193 gazette

  An object of the present invention is to make it possible to execute beam irradiation and image photographing at a pinpoint at the time when the breathing bottom comes out without significantly extending the treatment time. At this time, a stable respiratory state can be maintained for a long time without imposing a burden on the patient.

The present invention has been made to achieve the above object. The respiratory synchronization device according to the present invention is
A respiration measuring unit that detects a patient's respiration over time as a respiration signal;
Calculating a respiratory phase signal and a respiratory cycle signal from the respiratory signal, passing the respiratory phase signal to the tempo control unit, and passing the respiratory cycle signal to the respiratory bottom prediction unit;
A tempo control unit that generates a tempo adjustment signal that variably adjusts the music tempo according to the respiratory phase signal, and sends the tempo adjustment signal to the acoustic control unit;
A sound control unit that generates music with a tempo adjusted according to a tempo adjustment signal from the tempo control unit,
This is a breathing synchronization device that predicts the appearance timing of the next breathing bottom from the past breathing cycle data and instructs the operation of the device in accordance with the appearance timing. In the respiratory synchronizer,
The respiratory signal of the patient and the transducer related to the tempo adjustment signal are mutually pulled in phase .

  First, by utilizing the present invention, the patient's breathing is induced and the respiratory cycle is stabilized. In addition, a breathing bottom is accurately predicted, and therefore, pinpoint beam irradiation and image shooting at the breathing bottom become possible, and irradiation accuracy and image quality are greatly improved.

  Embodiments according to the present invention will be described below with reference to the drawings.

About respiratory synchronization method.
First, as a premise of the description of the embodiment, the respiratory synchronization method will be described with reference to FIGS. 1, 2, 3, and 4. In the respiratory synchronization method, a threshold value is set for the respiratory signal, and the gate signal is turned on when the respiratory signal satisfies the requirements regarding the threshold value. The requirements are that the respiratory signal is at a level below the threshold, the respiratory signal is at a level above the threshold, the respiratory signal is at an intermediate level between the two thresholds, and so on. The gate signal is a signal for controlling beam irradiation and image shooting. When the gate signal is on, beam irradiation and image shooting are executed. When the gate signal is off, beam irradiation and image shooting are performed. Is not executed. FIG. 1 shows an example of the transition of a gate signal in the case where the respiration signal is at a level below a threshold.

  Here, as shown in FIG. 2, if the threshold setting is not appropriate, that is, if the level is set to a level significantly higher than the breathing bottom, beam irradiation or image capturing is performed even at a timing shifted from the breathing bottom. Can be executed. Therefore, as shown in FIG. 3, when the threshold is set to a level near the breathing bottom, the time interval of the on state of the gate signal is narrowed, and the beam irradiation and image capturing period approaches the present time of the breathing bottom, This problem can be avoided. However, as shown in FIG. 4, when the breathing itself is unstable, the threshold is set at a level near the bottom of the breathing, so that the frequency of appearance of the ON state of the gate signal is remarkably lowered, and the treatment time is greatly extended. Leads to. This must be avoided because it increases the burden on the patient.

  Therefore, in the respiratory synchronization method, the patient's breathing is required to be stable in order to perform treatment with a balance between irradiation efficiency and irradiation accuracy. Therefore, in the present invention, in an actual situation where the physiological behavior of a human changes every moment and is difficult to stabilize, the interaction between the human and the machine that controls the human is performed in order to stabilize the difficult behavior. Is introduced.

  Specifically, the physiological behavior rhythm and the machine rhythm are mutually attracted by a method called mutual pulling, and the physiological behavior is stabilized while allowing some variation in physiological behavior. At the same time, by predicting the cycle of the next physiological behavior, an operation completely synchronized with the physiological behavior of the radiation therapy apparatus or the image diagnostic apparatus is realized. In other words, a dual control method of stabilizing physiological behavior and predicting physiological behavior is used.

Embodiment 1 FIG.
FIG. 5 is a block diagram showing the configuration of the respiratory-guided radiation therapy apparatus 100 (hereinafter referred to as “radiation therapy apparatus 100”) according to the first embodiment of the present invention. In the radiotherapy apparatus 100, the patient's breathing is induced by letting the patient listen to music and tapping according to the music. As a result, the patient's respiratory cycle is stabilized at a constant value, and radiotherapy that is completely synchronized with respiration can be performed.

  The radiotherapy apparatus 100 includes an acoustic control unit 101, a respiration measurement unit 102, a respiration signal processing unit 103, a tempo control unit 104, a radiation generation unit 105, an irradiation unit 106, an irradiation control unit 107, a respiration bottom prediction unit 108, and A switch 109 is included. First, schematic points (three points) of the first embodiment by the radiation therapy apparatus 100 including these components will be described.

  First, in the tempo control unit 104, the solution of the differential equation (formula 1 below) of the phase oscillator that is a respiration model is numerically calculated in real time, and the music is played in accordance with the period of the differential equation solution. Is generated and output from the sound control unit 101. A perturbation term corresponding to the difference between the phase of the respiratory signal of the patient and the phase of the phase oscillator is inserted in the differential equation of the phase oscillator of Formula 1. As a result, the patient's breathing and the phase oscillator are drawn into each other through music. Since the tempo of music changes based on the phase relationship between both breathing and the phase oscillator, the tempo is not constant and has some kind of fluctuation. Such a case in which one side is not forcedly drawn into the other constant rhythm, but one side and the other draws to the middle point in a manner that approaches each other, is called mutual drawing. By mutual pulling, pulling can be continued stably.

  The second point is that a tapping operation in accordance with music is introduced. The frequency of pulling in music rhythm and breathing rhythm dramatically increases by combining auditory stimulation with music and body movements that match the music. As the body movement, tapping that moves a finger is sufficient, and it is sufficiently applicable to the fields of radiation therapy and diagnostic imaging. By introducing tapping, retraction occurs even if the patient is not conscious of breathing to the music. This leads to relief of the patient's compulsion. The patient can realize the tapping operation by pressing (tapping) the switch 109, for example. The tapping operation may take other forms.

  The third point is that a breathing bottom is predicted in a state where breathing is stabilized by the above-described two ideas. The respiratory bottom prediction unit 108 obtains information about the respiratory cycle from the respiratory signal processing unit 103, predicts the next respiratory cycle from the accumulated past respiratory cycle, and predicts the appearance timing of the respiratory bottom. Since the ideal timing of beam irradiation and image capturing is the time when the breathing bottom comes out, beam irradiation and image capturing at that timing can greatly improve accuracy. Since the respiration is in a stable state, the next respiration cycle can be easily predicted by using existing estimation methods such as a moving average, an autoregressive model, and a Kalman filter.

  Then, it shows about the structure of each part. In the following, a radiotherapy apparatus will be described, but the embodiment of the present invention can also be used in an image diagnostic apparatus. In this case, for example, an image photographing unit (etc.) is set instead of the irradiation unit 106. Furthermore, the embodiment of the present invention can also be used in a nuclear magnetic resonance diagnostic imaging apparatus, an ultrasonic diagnostic imaging apparatus, or the like.

  The radiation generator 105 is an accelerator that accelerates radiation. Examples of the type of accelerator include a synchrotron and a linear accelerator. The synchrotron generates and accelerates protons and carbon beams, and the linear accelerator generates and accelerates electron beams and X-rays.

  The irradiation unit 106 is a device for irradiating the patient with radiation. For example, it is composed of a collimator and a filter for forming an irradiation field.

  The irradiation control unit 107 controls the radiation generation unit 105 and the irradiation unit 106 based on a gate signal described later.

  The respiration measurement unit 102 is, for example, a position measurement camera and its controller, and detects a position change accompanying respiration of a marker attached to the patient's body surface as a respiration signal. In addition, as a respiratory signal measurement sensor, a band-type respiratory pickup, a thermistor, a strain gauge, a laser displacement meter, or the like that incorporates an elastic variable resistance element can be used.

  The respiration signal processing unit 103 calculates the phase and period from the respiration signal. The calculation of the phase is detected from the positional relationship of the current sample point with respect to the previous respiratory cycle. The period is obtained by calculating the interval between the breathing bottoms. The respiratory phase is transferred to the tempo control unit 104, and the respiratory cycle is transferred to the respiratory bottom prediction unit 108.

The tempo control unit 104 calculates the solution (θ ₁ ) of the phase oscillator (Formula 1), which is a breathing model, in real time, generates the music tempo according to the period of the phase oscillator, and varies the music tempo. A tempo adjustment signal for adjustment is sent to the acoustic control unit 101.

  In order to generate the music tempo from the period of the phase oscillator, first, the number of waves per minute is calculated from the period of the phase oscillator. Next, the number of waves per minute is multiplied by the number of beats that make up one measure to obtain the music tempo. For example, if the song has a period of 4 seconds and a ¼ time signature, the number of waves per minute is 15 (times / minute), the number of beats constituting one bar is 4 (beats), and 60 (BPM) : Beat Per Minute) becomes the music tempo. In this way, by reflecting the period of the phase oscillator in the tempo of the music, the phase oscillator and the patient's breathing are mutually drawn through the music. Note that respiration and respiration can be performed by other nonlinear vibrators, and the phase vibrator is an example.

The relationship between the music rhythm and the patient's respiratory rhythm will be schematically described using the following equations 1 and 2. Note that Equation 2 models patient breathing for explanation, and is not actually calculated numerically. θ ₁ is the phase of music (phase oscillator), ω ₁ is the natural frequency of music (phase oscillator), θ ₂ is the phase of respiration, and ω ₂ is the natural frequency of respiration. ξ ₁ is a coefficient representing the strength of coupling between music (phase oscillator) and respiration. When ξ ₁ is increased, the music tempo is likely to change according to breathing, and vice versa. ξ ₂ is a coefficient representing the internal state of the patient. For example, ξ ₂ may be increased by a tapping operation in accordance with music (described later). Increasing ξ ₂ tends to change the breathing tempo according to music, and vice versa.

Consider the behavior of Equation 1. When θ ₂ is larger than θ ₁ , that is, when breathing is in phase with music, the second term on the right side of Equation ₁ becomes positive, and θ ₁ approaches θ ₂ in due course. That is, the music tempo is accelerated and the music phase approaches the breathing phase. When θ ₂ is smaller than θ ₁ , that is, when respiration is out of phase with music, the second term on the right side of Equation ₁ becomes negative, and θ ₁ approaches θ ₂ in due course. That is, the music tempo is slowed down and the music phase approaches the breathing phase.

Consider the behavior of Equation 2. If θ ₁ is greater than θ ₂ , that is, if the music is more advanced in phase than respiration, the second term on the right side of Equation 2 is positive, and θ ₂ is expected to approach θ ₁ in due course. That is, it is expected that the breathing tempo will increase and the breathing phase will approach the music phase. When θ ₁ is smaller than θ ₂ , that is, when music is delayed in phase from respiration, the second term on the right side of Equation 2 becomes negative, and θ ₂ is expected to approach θ ₁ before long. In other words, it is expected that the breathing tempo will slow down and the breathing phase will approach the music phase. As described above, by associating the period of the phase oscillator with the tempo of music, mutual entrainment between the phase oscillator and the patient's breath through the music is established.

  The breathing bottom prediction unit 108 estimates the next breathing cycle in the future from the past breathing cycle, and predicts the appearance timing of the breathing bottom. Further, the gate signal is turned on before and after the time when the next breathing bottom is predicted, and is turned off at other times. Here, the beam can be extracted from the accelerator only when the gate signal is on. In other words, it can be said that the gate signal indicates a period during which the affected part can be irradiated with radiation. The breathing bottom is the most suitable timing for irradiation. In this case, the most suitable timing for irradiation refers to a timing at which the affected part that moves due to breathing or the like is at substantially the same position as when the treatment is planned. The width of the gate signal may be about the same as or slightly larger than the width of the beam (spill width).

For example, an autoregressive (AR) model or a moving average (ARMA) model is used as the prediction algorithm. The autoregressive model is described as Equation 3 below.

The respiratory cycle sequentially obtained from the respiratory signal processing unit 103 is accumulated from the previous _one before breath (y _n-1 ) to the past p before breath (y _n-p ). Next respiratory cycle (y _n ) is estimated. Using the (p + 1) pieces of respiratory cycle data, it is necessary to fit the left side and the right side of Equation 3 by the least square method in advance to determine the coefficients a _{0 to} a _p . _xn represents a noise term, and similarly, a value needs to be set in advance. Once the coefficients a _{0 to} a _p are calculated, they can be used as fixed values as they are, but each time a new respiratory cycle is obtained, the coefficients a _{0 to} a _p may be sequentially recalculated to use new ones. Further, a Kalman filter may be used as a prediction algorithm, or a moving average of past respiratory cycles may be used.

Therefore, as a prediction algorithm,
(1) Simple extrapolation method,
(2) Moving average method,
(3) autoregressive model,
(4) Kalman filter (calculated every time a ₀ ... A _p is obtained for the respiratory cycle),
Etc. can be used.

  The sound control unit 101 includes a sound source data storage unit, a player, and a speaker, and can arbitrarily adjust the tempo according to an external signal. There is no restriction on the music data format, and the tempo control can be realized by extending or shortening the time between the musical notation. For example, when the sound source data is so-called MIDI data, the interval between the musical score and the musical score may be controlled for each musical score. If the time interval changes for each musical score, a sense of incongruity can be felt, and the tempo may be changed every fixed time or every bar period of music.

  The switch 109 is a switch for tapping operation. By tapping (continuously tapping) the switch, the patient can realize a finger tapping operation in accordance with music.

  Next, with reference to FIG. 6, processing in which the radiotherapy apparatus 100 shown in FIG. 5 induces patient respiration upon irradiation with radiation will be described. FIG. 6 is a flowchart showing a process in which the radiation therapy apparatus 100 induces patient respiration.

First, at S1, the patient's breathing at rest is measured for a certain period of time, and the natural frequency (ω ₁ ) of the music (phase oscillator) is determined. That is, the initial value of the music tempo is determined. At the same time, the respiration bottom prediction unit 108 determines a coefficient in a prediction model (for example, an autoregressive model) for predicting the appearance timing of the respiration bottom.

  Next, in S2, the sound control unit 101 is operated to start playing music at the tempo. At the same time, the respiration measurement unit 102 measures the respiration of the patient and generates a respiration signal.

  In step S <b> 3, the respiration signal processing unit 103 calculates a respiration phase based on the respiration signal received from the respiration measurement unit 102. The phase calculation is performed at regular intervals. In S4, the respiratory cycle is calculated. A cycle calculation is performed each time a bottom of respiration is detected.

  Next, in S5, the tempo calculation unit 104 numerically calculates the solution of the phase vibrator. For example, a numerical calculation using a fourth-order Runge-Kutta method is executed by a computer program. The period of the phase oscillator is calculated, and the music tempo is determined from the period.

  Next, in S6, the respiration bottom prediction unit 8 predicts the next respiration bottom based on the respiration cycle received from the respiration signal processing unit 103, and generates a gate signal.

  When S5 ends, the process returns to S3. When S6 ends, the process returns to S4, and the above procedure is repeated until the treatment ends.

  The effects of the first embodiment will be described based on FIG. In the conventional respiratory synchronization method, a threshold is set in the vicinity of about one third from the bottom of Peak to Peak of the respiratory amplitude, and when the respiratory signal falls below the threshold, the gate signal is turned on as shown in the lower part of FIG. It was. In this method, the beam is irradiated even at a location deviated from the bottom. In order to increase the irradiation accuracy, it is necessary to bring the threshold close to the breathing bottom. However, if the patient's respiratory amplitude is unstable, lowering the threshold significantly extends the treatment time. According to the first embodiment, when breathing is induced to stabilize the cycle and the breathing bottom is predicted, beam irradiation at the pinpoint at the breathing bottom becomes possible (FIG. 7 (2)), and the irradiation accuracy is greatly improved. improves.

Embodiment 2. FIG.
The second embodiment includes a configuration for guiding a patient's breathing to a preset target breathing cycle. Guidance to the target respiratory cycle is realized by creating a mutual drawing state in multiple stages. Specifically, the mutual respiration state of the patient's breathing and the phase oscillator is determined, and if mutual entrainment is achieved, the natural frequency ω ₁ of the phase oscillator is changed slightly closer to the target period to change Induces mutual retraction. By repeatedly executing the above, the patient's breathing can be guided to an arbitrary target period.

  FIG. 8 is a block diagram showing a configuration of a respiratory-guided radiation therapy apparatus 200 (hereinafter referred to as “radiation therapy apparatus 200”) according to the second embodiment of the present invention. In the radiotherapy apparatus 200, a determination unit 201 and a target value input unit 202 are newly provided with respect to the radiotherapy apparatus 100 of the first embodiment. With the addition of these configurations, the tempo calculation unit 104 performs a new operation.

  Hereinafter, the configuration and operation of the radiation therapy apparatus 200 will be described. However, since the configuration and operation other than those described below are the same as those of the radiation therapy apparatus 100 (FIG. 5) according to the first embodiment, description thereof will be omitted.

  First, the target value input unit 202 is a device that inputs a target value of a patient's respiratory cycle, and is, for example, a keyboard, a mouse, a numerical dial, or the like. As described in the first embodiment, since the patient's respiratory cycle and the tempo are correlated, the rhythm of the target music is input instead of the patient's respiratory cycle, and the target respiratory cycle You may ask for.

The determination unit 201 determines the respiration state of the patient's respiration and the phase oscillator. In the present embodiment, it is assumed that the pull-in is established when the phase difference between the phase (θ ₁ ) of the phase oscillator and the phase (θ ₂ ) of respiration becomes a predetermined value or less. At this time, the tempo calculation unit 104 uses a part of the difference between the period of the phase oscillator at the time of mutual pulling and the target respiratory cycle input from the target value input unit 202 as the natural vibration of the phase vibrator at the time of mutual pulling. It is added to the number ω _1. For example, when the difference is 4S, a part of the difference (2S) is converted from the period to the frequency and added to the natural frequency ω ₁ of the phase vibrator at the time of mutual drawing. As a result, the natural frequency ω ₁ of the phase vibrator is changed.

In the next step, a part (for example, S) of the remaining 2S of the difference is converted from the period to the frequency and added to the natural frequency ω ₁ of the phase vibrator. In this manner, by gradually changing the natural frequency ω ₁ of the phase vibrator to gradually approach the target period, the mutual pulling state is induced step by step. As a result, the patient's breathing is guided to the final target breathing cycle.

  In addition, by making the patient's breathing coincide with the operation cycle and initial phase of the accelerator, it can be expected that the treatment efficiency will be greatly improved by shortening the time.

  According to the second embodiment, the natural frequency of the phase oscillator is corrected in accordance with the difference between the period of the phase oscillator and the target respiratory period, and the music tempo to be given to the patient based on the corrected period of the phase oscillator Therefore, it is possible to realize a reasonable reciprocal pulling in accordance with the patient's breathing state and to guide the patient's breathing in an arbitrary cycle.

Embodiment 3 FIG.
FIG. 9 is a block diagram showing a configuration of a respiratory-guided radiation therapy apparatus 300 (hereinafter referred to as “radiation therapy apparatus 300”) according to the third embodiment of the present invention. In the radiotherapy apparatus 300, a stimulus presentation unit 110 that is connected to the switch 109 is newly provided in the radiotherapy apparatus 100 of the first embodiment.

  Hereinafter, the configuration and operation of the radiation therapy apparatus 300 will be described. However, since the configuration and operation other than those described below are the same as those of the radiation therapy apparatus 100 (FIG. 5) according to the first embodiment, description thereof will be omitted.

  The stimulus presentation unit 110 is a means for presenting timing information generated by the patient pressing (tapping) the switch to the patient himself / herself. As a means for presenting (stimulus presenting unit 110), a drum sound may be put on music separately. Further, as a means for presenting, a light stimulus or a vibration stimulus may be used.

  In this way, by feeding back timing information from the patient's switch to the patient himself / herself, it is possible to improve the pull-in rate and stability of mutual pull-in.

Other embodiments.
In the above-described embodiment, it has been described that the patient's breathing is induced using the tempo of the music to be reproduced. However, the present invention is not limited to music, and may be, for example, slow flickering of light or vibrations of a patient's limbs. In the first to third embodiments, the radiotherapy apparatus has been described. However, the present invention is not limited to this, and the present invention can be used for an image diagnostic apparatus by replacing beam irradiation with image capturing. Similarly, it can be used for a nuclear magnetic resonance diagnostic apparatus and an ultrasonic diagnostic apparatus.

  Note that the operation of the radiotherapy apparatus described in the first to third embodiments can be realized by, for example, a computer program that realizes the processing of the flowchart shown in FIG. Therefore, the computer program itself that performs such an operation is also included in the scope of the present invention. Such a computer program can be recorded on an optical disk such as a CD or DVD, a magnetic recording medium such as a flexible disk, or a semiconductor recording medium such as a flash memory. Further, such a computer program can be transmitted via a network such as the Internet.

An example of transition of a gate signal in the case where the requirement that the respiration signal is at a level equal to or lower than a threshold value is shown. An example of the transition of the gate signal in the case where the respiration signal is at a level equal to or lower than the threshold value is shown, but the threshold value is not appropriately set. An example of transition of a gate signal in the case where the respiration signal is at a level equal to or lower than a threshold value is shown, and an example in which the respiration signal is stable. An example of the transition of the gate signal in the case of the requirement that the respiratory signal is at a level equal to or lower than the threshold value is shown, but is an example in which the respiratory signal is unstable. It is a block diagram which shows the structure of the respiration induction type radiotherapy apparatus of Embodiment 1 which concerns on this invention. 5 is a flowchart illustrating processing in which the radiation therapy apparatus induces patient respiration in the first embodiment. It is an example of transition of a respiration signal and a gate signal at the time of using Embodiment 1. It is a block diagram which shows the structure of the respiration induction type radiotherapy apparatus of Embodiment 2 which concerns on this invention. It is a block diagram which shows the structure of the respiratory induction type radiotherapy apparatus of Embodiment 3 which concerns on this invention.

Explanation of symbols

100, 200, 300 Radiotherapy device, 101 Acoustic control unit, 102 Respiration measurement unit, 103 Respiration signal processing unit, 104 Tempo control unit, 105 Radiation generation unit, 106 Irradiation unit, 107 Irradiation control unit, 108 Respiration bottom prediction unit, 109 switch, 110 stimulus presentation unit, 201 determination unit, 202 target value input unit.

Claims (3)

A respiration measuring unit that detects a patient's respiration over time as a respiration signal;
Calculating a respiratory phase signal and a respiratory cycle signal from the respiratory signal, passing the respiratory phase signal to the tempo control unit, and passing the respiratory cycle signal to the respiratory bottom prediction unit;
A tempo control unit that generates a tempo adjustment signal that variably adjusts the music tempo according to the respiratory phase signal, and sends the tempo adjustment signal to the acoustic control unit;
A sound control unit that generates music with a tempo adjusted according to a tempo adjustment signal from the tempo control unit,
In the respiratory synchronization device that predicts the appearance timing of the next breath bottom from the past breathing cycle data and instructs the operation of the device according to the appearance timing,
A respiratory synchronization device characterized in that a respiratory signal of a patient and a vibrator related to a tempo adjustment signal perform mutual pulling in phase . The natural frequency of the vibrator related to the tempo adjustment signal is changed in a plurality of stages toward the target frequency, and mutual pulling in the phase is generated in multiple stages. Breathing synchronizer.   The respiratory synchronization apparatus according to claim 1 or 2, further comprising a switch for the patient to perform tapping according to music.

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