Detailed Description
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.
It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, these information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present invention. The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination", depending on the context.
In order to correct artifacts in PET scan images due to respiratory motion of a subject when a PET/CT apparatus is used to scan the lungs of the subject, the respiratory gating apparatus may be used to detect the respiratory motion of the subject, thereby correcting the scan images according to the detection result. The respiratory motion is the motion of regular expansion and contraction of the thoracic cavity caused by the relaxation and contraction of respiratory muscles, so the basic working principle of the respiratory gating device is to obtain respiratory motion data in the whole respiratory process by detecting the alternating motion and output gating signals, so that PET/CT equipment can correct PET scanning images according to the respiratory motion data and the gating signals, thereby effectively fusing the PET scanning images with the CT images and removing artifacts in the scanning images. The present invention will be described in detail with reference to specific examples.
Referring to fig. 1, a block diagram of an embodiment of the respiratory gating apparatus of the present invention is shown:
the respiratory gating apparatus may include: respiratory motion acquisition device 110 and gating signal output device 120.
The respiratory motion acquisition device 110 is configured to obtain acceleration data representing respiratory motion of a subject through an acceleration sensor, and transmit the acceleration data to the gating signal output device in a wireless manner.
In an optional implementation manner, the respiratory motion acquisition device 110 may acquire acceleration data, which is acquired by the acceleration sensor and used for characterizing the respiratory motion of the subject, in a preset detection period, and transmit the acquired acceleration data through the first antenna.
Wherein, the preset detection period can be the same as the scanning period of the PET/CT device; the acceleration sensor can be integrated in the respiratory motion acquisition device 110, or can be set independently of the respiratory motion acquisition device 110, and no matter what way the acceleration sensor is set, the acceleration sensor only needs to be ensured to acquire the respiratory motion data of the detected person and can transmit the acquired acceleration data to the respiratory motion acquisition device 110 for processing; the transmission frequency adopted by the wireless mode of communication between the respiratory motion acquisition device 110 and the gate control signal output device 120 may be 2.4GHz, that is, the first antenna may adopt 2.4GHz as the transmission frequency of the acceleration data.
And a gate control signal output device 120, configured to output a gate control signal according to the acceleration data after receiving the acceleration data.
In an alternative implementation manner, the gating signal output device 120 may receive the acceleration data transmitted by the first antenna through the second antenna, and after the acceleration data is integrated twice with respect to time, convert the acceleration data into displacement data, where the displacement data represents a situation that an amplitude of the respiratory motion of the subject in a preset detection period changes with time, so that it may be detected whether the respiratory motion of the subject in each respiratory period is within a preset amplitude range according to the displacement data, where the preset amplitude range is an amplitude range corresponding to a predefined normal respiratory motion, and output the gating signal with a preset pulse width in the detected respiratory period of the normal respiratory motion, where the preset pulse width may be 10ms, for example, and output the gating signal with a maximum amplitude corresponding to the inspiratory motion of each respiratory period in advance, or the gating signal may be output at a minimum amplitude corresponding to the expiratory motion for each respiratory cycle.
By applying the respiratory gating equipment provided by the embodiment of the invention, when the respiratory movement of the detected person is detected, the respiratory movement acquisition device can be attached to the body of the detected person, so that the acceleration data representing the respiratory movement of the detected person can be accurately acquired through the acceleration sensor, and after the acceleration data is transmitted to the gating signal output device in a wireless mode, the acceleration data can be analyzed and a gating signal can be output, so that the respiratory movement of the detected person can be accurately detected, and meanwhile, the gating signal capable of effectively correcting a scanning image can be provided for the PET/CT equipment.
Referring to fig. 2A, a block diagram of another embodiment of the respiratory gating apparatus of the present invention is shown, which discloses an exemplary structure of a respiratory motion acquisition apparatus 110 and a gating signal output apparatus 120 in detail based on the embodiment shown in fig. 1:
first, the structure of the respiratory motion acquisition apparatus 110 is described:
the respiratory motion acquisition apparatus 110 may include: the device comprises an acceleration sensor 111, a filtering and level converting circuit 112, a first MCU113, a wireless transmitting module 114 and a power supply module 115.
The acceleration sensor 111 is configured to collect acceleration data representing respiratory movement of the subject in a preset detection period, and transmit the acceleration data to the filtering and level converting circuit 112.
In this embodiment, the preset detection period may be the same as the scanning period of the PET/CT apparatus. Because the respiratory motion is composed of the reciprocating motion of the chest, the respiratory motion of each respiratory cycle is composed of one expiration and one inspiration, and the expiration time is usually slightly longer than the inspiration time, when the acceleration sensor is attached to the chest part of the body of the subject, the acceleration data representing the respiratory motion can be detected by the acceleration sensor, and according to the periodic characteristics of the respiratory motion, the acceleration data in the preset detection cycle can be represented as a quasi-sinusoidal curve, as shown in fig. 2B. The acceleration sensor may transmit the collected acceleration data in the form of a voltage signal to the filtering and level shifting circuit 112.
And the filtering and level converting circuit 112 is configured to perform filtering processing on the acceleration data acquired by the acceleration sensor 111, perform level conversion on the filtered acceleration data to make a voltage value of an electrical signal corresponding to the acceleration data consistent with a working voltage value of the first MCU, and transmit the level-converted acceleration data to the first MCU 113.
Because the acceleration data collected by the acceleration sensor 111 may have interference such as noise, a high-pass filter or a low-pass filter may be preset in the filtering and level converting circuit 112 as required, and when the acceleration data is received, the acceleration data is firstly filtered so as to eliminate noise and obtain a smooth acceleration curve; in addition, when the acceleration data is transmitted by using the voltage signal, if the acceleration data is inconsistent with the operating voltage of the first MCU113, it needs to be level-converted so as to ensure that the first MCU113 can process the acceleration data, for example, if the voltage value of the voltage signal of the acceleration data is plus or minus 5V and the operating voltage of the first MCU113 is plus or minus 3V, the voltage value of the voltage signal of the acceleration data can be scaled proportionally according to the ratio between the two voltages so as to reach the available voltage of the first MCU 113.
The first MCU113 is configured to transmit the acquired acceleration data to the wireless transmitting module 114.
And a wireless sending module 114, configured to send the received acceleration data through the first antenna.
In this embodiment, the first antenna may use 2.4GHz as the transmission frequency of the acceleration data.
And the power supply module 115 is used for supplying power to the respiratory motion acquisition device through a battery and managing the working process of the battery.
In this embodiment, the management functions of the power module 115 may include managing charging and discharging of a battery, managing a short circuit of the battery, and performing overload protection on the battery, and the specific management process is similar to the battery management process in the prior art and is not described herein again. In an alternative implementation, the battery used by the respiratory motion acquisition apparatus 110 may be a lithium battery.
Next, the structure of the gate control signal output device 120 will be described:
the gate signal output device 120 may include: a wireless receiving module 121, a second MCU122, a gate control output module 123, and a CAN (controller area network) bus 124.
The wireless receiving module 121 is configured to receive, through a second antenna, acceleration data transmitted by the first antenna, and transmit the acceleration data to the second MCU.
The transmission frequency of the first antenna corresponding to the wireless transmission module 114 is 2.4GHz, and the reception frequency of the second antenna may be 2.4GHz accordingly. In this embodiment, as long as it is ensured that the same frequency is used in the wireless communication process between the first antenna and the second antenna, the specific value of the used frequency is not limited in this embodiment.
The second MCU122 is configured to convert the acceleration data into displacement data, and detect whether the respiratory motion in each respiratory cycle is within a preset amplitude range according to the displacement data, where the preset amplitude range is an amplitude range corresponding to a predefined normal respiratory motion.
In this embodiment, the working voltage of the second MCU122 may be set to be consistent with that of the first MCU113, so that the second MCU122 can directly process the received acceleration data.
After receiving the acceleration data, the second MCU122 may perform two-time integration on the acceleration data to obtain corresponding displacement data, where the displacement data represents a time variation of an amplitude of a respiratory motion of the subject in a preset detection period, and is consistent with the acceleration data, and the displacement data may also be represented as a quasi-sinusoidal curve.
In this embodiment, an amplitude range corresponding to the normal breathing motion may be predefined, and the amplitude range includes an upper limit value and a lower limit value. Therefore, when detecting whether the respiratory motion is within the preset amplitude range, the second MCU122 may first calculate a maximum value or a minimum value of the displacement data within the respiratory cycle of the normal respiratory motion, where the maximum value is a maximum amplitude corresponding to the inspiratory motion of the normal respiratory motion, and the minimum value is a minimum amplitude corresponding to the expiratory motion of the normal respiratory motion, and then determine that the respiratory motion is not within the preset amplitude range when the maximum value exceeds an upper limit value of the amplitude range or the minimum value is lower than a lower limit value of the amplitude range, otherwise, the respiratory motion is within the preset amplitude range. In addition, except for predefining an amplitude range corresponding to normal respiratory motion, respiratory gating equipment can be adopted to perform respiratory training on the detected person before respiratory gating is performed on the detected person formally, so that the average value of the maximum amplitude corresponding to inspiratory motion of the detected person in a plurality of respiratory cycles is obtained and used as the upper limit value of the amplitude range, and the average value of the minimum amplitude corresponding to expiratory motion is used as the lower limit value of the amplitude range. The amplitude range corresponding to the normal breathing movement is set by specifically adopting any manner, which is not limited in this embodiment.
And the gating output module 123 is configured to output a gating signal with a preset pulse width in the respiratory cycle of the normal respiratory motion detected by the second MCU.
In an alternative implementation: the gating output module 123 may output the gating signal with the preset pulse width at a time corresponding to a maximum value of the displacement data (i.e., a maximum amplitude corresponding to the inspiratory motion) in the respiratory cycle of the normal respiratory motion, or output the gating signal with the preset pulse width at a time corresponding to a minimum value of the displacement data (i.e., a minimum amplitude corresponding to the expiratory motion) in the respiratory cycle of the normal respiratory motion, for example, the preset pulse width may be set to 10ms in this embodiment. In this embodiment, the gating signal may be preset to be output at the maximum value, or output at the minimum value, as long as it is ensured that one gating signal can be output in each respiratory cycle of normal respiratory motion. As shown in fig. 2C, a schematic diagram of the output of the gating signal of the respiratory motion in the present embodiment is shown, in fig. 2C, a quasi-sinusoidal curve of displacement data in several respiratory cycles is shown, and upper and lower limit values of the amplitude range indicated by dotted lines are shown, in fig. 2C, assuming that the gating signal is output at the maximum amplitude corresponding to the inspiratory motion of the normal respiratory motion, it is normal respiratory motion in the first respiratory cycle, and therefore the gating signal is output, and it is abnormal respiratory motion in the second respiratory cycle, and therefore the gating signal is not output.
Usually, the human body breathes about 16 to 20 times per minute, and when the breath number is too high or too low, it may indicate that the human body is abnormal. Therefore, in another alternative implementation manner, in combination with the gating signal output by the gating output module 123, the second MCU122 may further count the number of signals of the gating signal output by the gating output module 123 within a unit time (for example, one minute), and when the number of signals exceeds a preset number threshold, it indicates that the subject is abnormal in breathing, and at this time, the second MCU122 may control the gating output module 123 to stop outputting the gating signal and output an alarm message.
The CAN bus 124 is used for interacting respiratory motion data with the PET/CT device, wherein the respiratory motion data may include at least one of the following data: acceleration data output by the second MCU and displacement data obtained by converting the acceleration data; the PET/CT equipment inputs a preset pulse width of a gating signal to the respiratory gating equipment in advance, a preset amplitude range corresponding to normal respiratory motion and the like.
By applying the respiratory gating equipment provided by the embodiment of the invention, when the respiratory movement of the detected person is detected, the respiratory movement acquisition device can be attached to the body of the detected person, so that the acceleration data representing the respiratory movement of the detected person can be accurately acquired through the acceleration sensor, and after the acceleration data is transmitted to the gating signal output device in a wireless mode, the acceleration data can be analyzed and a gating signal can be output, so that the respiratory movement of the detected person can be accurately detected, and meanwhile, the gating signal capable of effectively correcting a scanning image can be provided for the PET/CT equipment.
Referring to fig. 3, a flow chart of an embodiment of the respiratory gating method of the present invention, which may be applied to the respiratory gating apparatus shown in fig. 1 or fig. 2A, includes the following steps:
step 301: the respiratory motion acquisition device obtains acceleration data representing respiratory motion of a detected person through an acceleration sensor, and transmits the acceleration data to the gating signal output device in a wireless mode.
In the step, the respiratory motion acquisition device acquires acceleration data which is acquired by the acceleration sensor and used for representing the respiratory motion of the detected person in a preset detection period; and transmitting the acceleration data through a first antenna.
In an alternative implementation: before the respiratory motion acquisition device transmits the acceleration data through the first antenna, the acceleration data can be subjected to filtering processing, and the filtered acceleration data is subjected to level conversion, so that the voltage value of an electric signal corresponding to the acceleration data is consistent with the preset working voltage value of the respiratory motion acquisition device.
Step 302: and the gating signal output device outputs gating signals according to the acceleration data after receiving the acceleration data.
In this step, the gate control signal output device receives the acceleration data transmitted by the first antenna through the second antenna, converts the acceleration data into displacement data, detects whether the respiratory motion in each respiratory cycle is within a preset amplitude range according to the displacement data, wherein the preset amplitude range is an amplitude range corresponding to predefined normal respiratory motion, and outputs a gate control signal with a preset pulse width in the detected respiratory cycle of the normal respiratory motion.
In an alternative implementation: the gating signal output device can calculate the maximum value or the minimum value of displacement data in a respiratory cycle of normal respiratory motion, wherein the maximum value is the maximum amplitude corresponding to the inspiratory motion of the normal respiratory motion, the minimum value is the minimum amplitude corresponding to the expiratory motion of the normal respiratory motion, and a gating signal with a preset pulse width is output at the moment corresponding to the maximum value, or the gating signal with the preset pulse width is output at the moment corresponding to the minimum value.
In another alternative implementation: the gate control signal output device may count the number of gate control signals output per unit time, and stop outputting the gate control signals and output the alarm information when the number of signals exceeds a preset number threshold.
In another alternative implementation: the gating signal output device CAN interact respiratory motion data with the PET/CT equipment through a CAN bus, wherein the respiratory motion data comprises at least one of the following data: acceleration data and displacement data obtained by converting the acceleration data; the preset pulse width of the gating signal input by the PET/CT equipment, the preset amplitude range corresponding to normal breathing movement and the like.
The specific implementation process of the above embodiment of the respiratory gating method is the same as that described in the foregoing embodiment of the respiratory gating apparatus, and is not described herein again.
Referring to fig. 4, a block diagram of an embodiment of the MCU of the present invention, which can be applied to a gating signal output device in a respiratory gating apparatus as shown in fig. 1 and fig. 2A, includes: an acquisition unit 410 and an output unit 420.
The acquiring unit 410 is configured to acquire acceleration data representing respiratory movement of a subject in a wireless manner in a preset detection period, where the acceleration data is acquired by an acceleration sensor;
an output unit 420, configured to output a gating signal according to the acceleration data.
In an alternative implementation, the output unit 420 may include (not shown in fig. 4):
the data conversion subunit is used for converting the acceleration data into displacement data;
the breath detection subunit is used for detecting whether the breath motion in each breath cycle is within a preset amplitude range according to the displacement data, wherein the preset amplitude range is an amplitude range corresponding to predefined normal breath motion;
and the signal output subunit is used for outputting a gating signal with a preset pulse width in the detected breathing cycle of the normal breathing movement.
In another optional implementation, the output unit may further include (not shown in fig. 4):
the amplitude value operator unit is used for calculating the maximum value or the minimum value of the displacement data in the respiratory cycle of the normal respiratory motion, wherein the maximum value is the maximum amplitude corresponding to the inspiratory motion of the normal respiratory motion, and the minimum value is the minimum amplitude corresponding to the expiratory motion of the normal respiratory motion;
the signal output subunit is specifically configured to output the gate control signal with the preset pulse width at a time corresponding to the maximum value, or output the gate control signal with the preset pulse width at a time corresponding to the minimum value.
In another optional implementation, the output unit may further include (not shown in fig. 4):
the signal counting subunit is used for counting the signal quantity of the gating signals output in unit time;
and the alarm output subunit is used for controlling the signal output subunit to stop outputting the gate control signal and outputting alarm information when the signal quantity exceeds a preset quantity threshold value.
In another optional implementation, the MCU may further include (not shown in fig. 4):
an interaction unit for interacting the respiratory motion data with the PET/CT device through the CAN bus, wherein,
the respiratory motion data comprises at least one of the following: the acceleration data and displacement data obtained by converting the acceleration data; the preset pulse width of the gating signal input by the PET/CT equipment and the preset amplitude range corresponding to the normal breathing motion.
In another optional implementation manner, the transmission frequency adopted by the wireless manner is 2.4 GHz.
The implementation process of the function and the action of each unit in the MCU is specifically described in the corresponding implementation process in the above device or method, and is not described herein again.
Referring to fig. 5, a schematic diagram of an application scenario of the embodiment of respiratory gating of the present invention:
fig. 5 includes: PET/CT devices and respiratory gating devices. The respiratory motion acquisition device of the respiratory gating equipment can be designed into a respiratory abdominal belt, and the respiratory abdominal belt can be fixed on the upper body of a detected person, for example, wound on the chest of the detected person in an adhesion mode so as to acquire respiratory motion data; the gating signal output device of the respiratory gating device CAN be designed as a data card which CAN be arranged on the PEC/CT device and CAN interact with the PEC/CT device via a CAN bus. The operation of the respiratory gating apparatus shown in fig. 5 is the same as that described above with respect to the embodiment of fig. 1-4, and will not be described again here.
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.
It will be understood that the invention is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.