Patent Application
20250072809
This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2023-138375, filed on Aug. 28, 2023; the entire contents of which are incorporated herein by reference.
Embodiments described herein relate generally to a medical image diagnosis apparatus, an X-ray computed tomography apparatus, and a medical image diagnosis system.
For examination purposes, medical image diagnosis apparatuses such as an X-ray computed tomography (CT) apparatus are used to generate medical images. Affected by organ motion as cardiac motion, for example, such medical images may include artifacts. To eliminate the influences of cardiac motion, for example, the X-ray CT apparatus performs retrospective ECG-gated image reconstruction. The retrospective ECG-gated image reconstruction is a technique to acquire projection data and measure electrocardiogram waveforms of a subject at the same time to acquire image data based on the electrocardiogram waveforms for reconstruction of CT images.
According to an embodiment, a medical image diagnosis apparatus includes processing circuitry. The processing circuitry obtains biological information as to a subject acquired by a biological monitor; obtain analysis information resulting from analysis of the biological information; and set an examination condition for capturing an image of the subject by a scan, based on the biological information and the analysis information.
Hereinafter, embodiments of an X-ray computed tomography (CT) apparatus will be described in detail with reference to the accompanying drawings. The X-ray CT apparatus is one example of medical image diagnosis apparatus.
The gantry 10 serves to irradiate a subject P (patient) with X-rays to detect the X-rays having transmitted the subject P for output to the console 30. The gantry 10 includes X-ray irradiation control circuitry 11, an X-ray generator apparatus 12, a detector 13, data acquisition circuitry (data acquisition system: DAS) 14, a rotational frame 15, and gantry driver circuitry 16.
In the gantry 10 of
The rotational frame 15 is an annular frame that supports the X-ray generator apparatus 12 and the X-ray detector 13 in opposing positions across the subject P to rotate at high speed on a circular path around the subject P under the control of the gantry driver circuitry 16 as described later.
The X-ray irradiation control circuitry 11 serves as a high-voltage generator that supplies a high voltage to an X-ray tube 12a. The X-ray tube 12a generates X-rays using the high voltage supplied from the X-ray irradiation control circuitry 11. Under the control of later-described scan control circuitry 33, the X-ray irradiation control circuitry 11 regulates an amount of X-rays to irradiate the subject P by regulating a supply of tube voltage and tube current to the X-ray tube 12a.
The X-ray irradiation control circuitry 11 also performs switching of wedges 12b. In addition the X-ray irradiation control circuitry 11 adjusts the X-ray irradiation range (fan angle or cone angle) by adjusting the aperture of a collimator 12c. In the present embodiment, the operator may manually switch multiple kinds of wedges.
The X-ray generator apparatus 12 includes the X-ray tube 12a, the wedges 12b, and the collimator 12c, to generate X-rays for irradiating the subject P.
The X-ray tube 12a is a vacuum tube to be applied with a high voltage from a not-shown high-voltage generator to irradiate the subject P with X-ray beams. Along with the rotation of the rotational frame 15, the X-ray tube 12a emits X-ray beams to the subject P. The X-ray tube 12a generates X-ray beams to diverge at a fan angle and a cone angle.
For example, under the control of the X-ray irradiation control circuitry 11, the X-ray tube 12a is able to successively emit X-rays to the entire perimeter of the subject P for full reconstruction and successively emit X-rays in a half-reconstructible irradiation range (180 degrees+fan angle) for half reconstruction. Under the control of the X-ray irradiation control circuitry 11, the X-ray tube 12a is also able to intermittently emit X-rays (pulsed X-rays) at a preset position (tube position).
The X-ray irradiation control circuitry 11 can modify the intensity of X-rays to be emitted from the X-ray tube 12a. For example, the X-ray irradiation control circuitry 11 increases the X-ray emission of the X-ray tube 12a in intensity at a particular tube position and decreases the X-ray emission of the X-ray tube 12a in intensity in a range outside the particular tube position.
The wedges 12b serve as X-ray filters that regulate an amount of X-rays emitted from the X-ray tube 12a.
Specifically, the wedges 12b are filters to allow the X-rays emitted from the X-ray tube 12a to transmit therethrough for attenuation, so that the subject P is irradiated with the X-rays from the X-ray tube 12a in a predefined distribution. The wedges 12b are formed of aluminum to have a given target angle and a given thickness, for instance. The wedge may be referred to as a wedge filter or a bow-tie filter.
The collimator 12c is slits for restricting the irradiation range of the X-rays after adjusted in amount by the wedges 12b under the control of the X-ray irradiation control circuitry 11.
The gantry driver circuitry 16 rotates the X-ray generator apparatus 12 and the detector 13 on the circular path around the subject P by rotating the rotational frame 15.
The detector 13 is a two-dimensional array detector (area detector) that detects the X-rays having transmitted the subject P. The detector 13 includes, for example, multiple arrays of X-ray detector elements for multiple channels arranged along the body axis (in the Z-axis direction in
Specifically, in the present embodiment the detector 13 includes a large number of X-ray detector element arrays, e.g., 320 arrays, in the body-axis direction of the subject P. The detector 13 is capable of detecting the X-rays having transmitted a large area of the subject P, e.g., an area including the lungs or the heart of the subject P.
The data acquisition circuitry 14 is a DAS that acquires projection data from detection data on the X-rays detected by the detector 13.
For example, the data acquisition circuitry 14 subjects X-ray-intensity distribution data detected by the detector 13 to amplification, A/D conversion, and sensitivity correction among the channels, to generate projection data and transmit the resultant projection data to the console 30. As an example, with respect to the X-rays successively emitted from the X-ray tube 12a during the rotation of the rotational frame 15, the data acquisition circuitry 14 acquires projection datasets corresponding to the entire perimeter (by 360 degrees).
The data acquisition circuitry 14 also transmits to the console 30 the projection datasets and the tube positions in association with each other. The tube positions serve as information representing the projection direction of the projection data. Preprocessing circuitry 34 as described later may perform sensitivity correction among the channels.
The couch 20 is an apparatus on which the subject P is to lie. As illustrated in
The gantry 10 performs, for example, a helical scan, i.e., scanning the subject P in a helical manner by rotating the rotational frame 15 while moving the couch top 22. Also, the gantry 10 performs a conventional scan i.e., scanning the subject P in a stationary position on the circular path by rotating the rotational frame 15 after moving the couch top 22. Further, the gantry 10 performs a step and shoot scan, i.e., performing a conventional scan in multiple scan areas while moving the couch top 22 in position with constant intervals.
The console 30 serves to allow an operator to manipulate the X-ray CT apparatus 1, and reconstruct X-ray CT image data based on the projection data acquired by the gantry 10. As illustrated in
The input circuitry 31 includes various elements, such as a mouse, a keyboard, a trackball, a switch, a button, and a joystick, with which the operator of the X-ray CT apparatus 1 inputs various kinds of instructions and settings. The input circuitry 31 transfers information representing the operator's instructions and settings to the processing circuitry 37.
For example, the input circuitry 31 receives an operator's input to select an examination for the subject P. The input circuitry 31 also receives a designation of a region on the image. In addition the input circuitry 31 may receive a scan condition for X-ray CT image data, a reconstruction condition for reconstructing X-ray CT image data, and an image processing condition for X-ray CT image data from the operator.
The display 32 serves as a monitor which the operator views. Under the control of the processing circuitry 37, the display 32 displays image data generated from the X-ray CT image data for the operator and a graphical user interface (GUI) that allows the operator to input various kinds of instructions and settings via the input circuitry 31.
Under the control of the processing circuitry 37, the scan control circuitry 33 controls the operations of the X-ray irradiation control circuitry 11, the gantry driver circuitry 16, the data acquisition circuitry 14, and the couch driver 21 to cause the gantry 10 to perform projection-data acquisition. Specifically, according to the scan condition set by the processing circuitry 37, the scan control circuitry 33 individually controls scanning for acquiring localizer radiographs (scanograms) and projection-data acquisition in main scanning to acquire images for use in diagnosis. Determination as to the scan condition by the processing circuitry 37 will be described below. In the present embodiment the X-ray CT apparatus 1 is capable of capturing two-dimensional and three-dimensional scanograms.
For example, the scan control circuitry 33 captures a two-dimensional scanogram of the subject P by consecutively scanning the subject P while moving the couch top 22 at constant speed, with the X-ray tube 12a remaining stationary at 0-degree position (frontward position relative to the subject P).
Alternatively, the scan control circuitry 33 captures a two-dimensional scanogram of the subject P by iteratively scanning the subject P in synchronization with intermittent movements of the couch top 22 while the X-ray tube 12a remains stationary at 0-degree position. The scan control circuitry 33 can capture a localizer radiograph of the subject P from an optional direction (e.g., lateral direction), in addition to the frontward direction.
Further, the scan control circuitry 33 can capture a three-dimensional scanogram of the subject P by acquiring the projection data of the entire perimeter of the subject P. For example, the scan control circuitry 33 can acquire the projection data of the entire perimeter of the subject P by a helical scan or non-helical scan.
The scan control circuitry 33 can perform a helical scan or a non-helical scan of a large area of the subject P, such as the entire chest region, the entire abdominal region, the whole upper body, and the whole body, at a lower dose than that of a main scan. Examples of the non-helical scan includes step and shoot scanning as described above.
As such, the scan control circuitry 33 can acquire the projection data of the entire perimeter of the subject P. This enables the image reconstruction circuitry 36 to reconstruct three-dimensional X-ray CT image data (volume data) and generate a localizer image based on the reconstructed volume data from an optional direction, as described below.
Dimension of localizer images to be captured, i.e., two-dimension or three-dimension may be set freely by the operator or set in advance depending on the items of an examination.
The preprocessing circuitry 34 subjects the projection data generated by the data acquisition circuitry 14 to correction processing including, for example, logarithm conversion, offset correction, sensitivity correction, and beam hardening correction, to generate corrected projection data.
Specifically, the preprocessing circuitry 34 generates corrected projection data of projection data of the localizer image generated by the data acquisition circuitry 14 and of projection data acquired by the main scan, and stores the corrected projection data in the storage circuitry 35.
The storage circuitry 35 stores therein various kinds of information, for example, the projection data generated by the preprocessing circuitry 34. Specifically, the storage circuitry 35 stores projection data of localizer images generated by the preprocessing circuitry 34 and projection data acquired for diagnosis purpose by the main scan.
The storage circuitry 35 further stores an examination-condition database (DB) 351. The examination-condition database 351 contains data for determining an examination condition of an X-ray CT examination. The examination condition refers to, for example, a scan condition and a reconstruction condition for obtaining an image of the subject by a scan. With reference to
In
In
As an example, the first row of the database in
Referring back to
Various reconstruction methods are available, including back projection, for example. Examples of the back projection include filtered back projection (FBP). Alternatively, the image reconstruction circuitry 36 can reconstruct X-ray CT image data by iterative reconstruction.
The image reconstruction circuitry 36 generates image data by performing various kinds of image processing to the X-ray CT image data. The image reconstruction circuitry 36 stores the reconstructed X-ray CT image data and the image data resulting from various kinds of image processing in the storage circuitry 35.
The processing circuitry 37 performs control over the X-ray CT apparatus 1 as a whole by controlling the operations of the gantry 10, the couch 20, and the console 30.
Specifically, the processing circuitry 37 causes the scan control circuitry 33 to control the gantry 10 to perform CT scans. The processing circuitry 37 causes the image reconstruction circuitry to control the console 30 to perform image reconstruction and image generation. The processing circuitry 37 also causes the display 32 to display various kinds of image data stored in the storage circuitry 35.
The electrocardiograph 40 is attached to the subject P to acquire electrocardiogram data from the subject P. The electrocardiograph 40 obtains electrocardiogram waveforms of the subject P from the electrocardiogram data. The electrocardiograph 40 transmits the electrocardiogram waveforms to the console 30. In the present embodiment, the electrocardiograph 40 transmits the electrocardiogram waveforms in real time. The console 30 stores the electrocardiogram waveforms in the storage circuitry 35 upon receipt from the electrocardiograph 40.
Namely, the storage circuitry 35 stores therein the electrocardiogram waveforms. Herein, a duration of one cycle of the electrocardiogram waveforms is normalized to zero to 100%, and each position in the duration represented by % is referred to as a cardiac phase. For example, in the cardiac phase, an indefinite duration from an R wave to the next R wave is normalized to zero to 100%.
The electrocardiograph 40 obtains analysis information by analyzing the electrocardiogram waveforms of the subject P and transmits it to the console 30. The console 30 receives and stores the analysis information from the electrocardiograph 40 in the storage circuitry 35. The electrocardiograph 40 may transmit the analysis information on the electrocardiogram waveforms at a timing later than the electrocardiogram waveforms. In this manner the electrocardiograph 40 can transmit the analysis information to the X-ray CT apparatus 1 even when it takes time for the analysis.
The analysis information includes diagnosis information and measurement information. The diagnosis information represents a clinical state of the subject. For example, the diagnosis information represents electrocardiographic findings of the subject P by the Minnesota code classification system, which is a coding system for expressing electrocardiographic findings in an objective and unified manner.
Examples of the diagnosis information include, but are not limited to, normal sinus rhythm, atrioventricular block, short PQ interval, pacemaker in operation, ventricular premature contraction, ventricular premature contraction (bigeminy), and atrial fibrillation.
The measurement information represents characteristics of biological information. The measurement information refers to, for example, information computable based on the electrocardiogram waveforms and representable by numerical values. Examples of the measurement information include, but are not limited to, PR (PQ) interval, RR interval, heart-rate variation, frequency of irregular pulse.
The overall structure and configuration of the X-ray CT apparatus 1 according to the present embodiment have been described above. With such features, the X-ray CT apparatus 1 of the present embodiment functions to obtain the analysis information as to the subject P and set a suitable examination condition based on the analysis information, depending on the clinical state of the subject P.
To implement such functions, the processing circuitry 37 executes a system control function 37a, a display control function 37b, a first obtaining function 37c, a second obtaining function 37d, and a setting function 37e, as illustrated in
The processing and functions to be performed by the elements of the processing circuitry 37, i.e., the system control function 37a, the display control function 37b, first obtaining function 37c, second obtaining function 37d, and setting function 37e in
The processing circuitry 37 serves as a processor that retrieves and executes the respective computer programs from the storage circuitry 35 to implement the functions corresponding to the computer programs. In other words, having retrieved the computer programs, the processing circuitry 37 includes the functions illustrated within the processing circuitry 37 of
The system control function 37a controls the overall operation of the X-ray CT apparatus 1 in a unified manner. For example, the system control function 37a controls the scan control circuitry 33 to perform a scan of the subject P according to a scan condition set by the setting function 37e as described later. For another example, the system control function 37a controls the image reconstruction circuitry 36 to perform an image reconstruction process under a reconstruction condition set by the setting function 37e.
The display control function 37b performs display control to display various kinds of information on the display. For example, the display control function 37b causes the display 32 to display image data generated based on the X-ray CT image data by the image reconstruction circuitry 36. For another example, the display control function 37b causes the display 32 to display a graphical user interface (GUI) that allows the operator to input various kinds of instructions and settings via the input circuitry 31.
In addition, the display control function 37b may cause the display 32 to display information representing an examination condition for examining the subject P.
The first obtaining function 37c obtains the electrocardiogram waveforms of the subject P acquired by the electrocardiograph 40. The electrocardiograph 40 is one example of biological monitor. The electrocardiogram waveform is one example of biological information. As an example, the first obtaining function 37c obtains the electrocardiogram waveforms of the subject P as transmitted in real time from the electrocardiograph 40 to the console 30.
The second obtaining function 37d obtains the analysis information resulting from the analysis of the electrocardiogram waveforms of the subject P. As an example, the second obtaining function 37d obtains the diagnosis information and the measurement information as transmitted from the electrocardiograph 40 to the console 30. The diagnosis information represents electrocardiographic findings of the subject P by the Minnesota code classification system. The measurement information represents, for instance, heart rate, PR interval, RR interval, or frequency of irregular pulse. The diagnosis information and the measurement information are exemplary analysis information.
The setting function 37e sets an examination condition based on the electrocardiogram waveforms obtained by the first obtaining function 37c and the diagnosis information and measurement information obtained by the second obtaining function 37d.
For example, the setting function 37e identifies a scan condition and a reconstruction condition corresponding to the diagnosis information obtained by the second obtaining function 37d, with reference to the examination-condition database 351 in the storage circuitry 35. The setting function 37e sets the identified scan condition and reconstruction condition according to the measurement information obtained by the second obtaining function 37d. The following will describe an operation of the setting function 37e, referring to
First, an example that the diagnosis information obtained by the second obtaining function 37d indicates “equal pulse (normal sinus rhythm) and heart rate of 65 bpm or less” is explained. In this case, the setting function 37e identifies a scan condition and a reconstruction condition associated with the diagnosis information “equal pulse (normal sinus rhythm) and heart rate of 65 bpm or less”, referring to the examination-condition database 351 in the storage circuitry 35. In the example of
Next, the setting function 37e sets a scan condition based on “irradiate only in middiastole” based on the measurement information obtained by the second obtaining function 37d. Likewise, the setting function 37e sets a reconstruction condition based on “reconstruct middiastole”. The following will describe an operation of the setting function 37e when the diagnosis information indicates “equal pulse (normal sinus rhythm) and heart rate of 65 bpm or less”, referring to
In the example of
The setting function 37e then predicts a time SP2 corresponding to the time SP1 in an RR interval following the duration RR1 on the premise that the RR intervals are uniform. The setting function 37e also determines an X-ray irradiation start time ES1 and an X-ray irradiation end time EE1 so that the time SP2 matches a time EC in the middle of an X-ray irradiation period and the subject P is irradiated with X-rays for the duration of 250 ms. In other words, the setting function 37e determines a scan timing ST1 included in the scan condition.
The setting function 37e sets an operation condition for the gantry 10 and the couch driver 21 to irradiate the subject P with X-rays at the set scan timing. In the present embodiment the operation condition is defined to be included in the scan condition.
The setting function 37e also sets a reconstruction timing RT1 included in the reconstruction condition to reconstruct image data of the subject P during the X-ray irradiation period under the set scan condition.
Next, an example that the diagnosis information obtained by the second obtaining function 37d represents “atrioventricular block” is described. In this case the setting function 37e identifies a scan condition and a reconstruction condition corresponding to the diagnosis information “atrioventricular block”, referring to the examination-condition database 351 in the storage circuitry 35. In the example of
The setting function 37e then sets a scan condition based on “correct HR threshold according to PR interval . . . ” based on the measurement information obtained by the second obtaining function 37d. Likewise, the setting function 37e sets a reconstruction condition based on “reconstruct immediately prior to P wave based on PR-interval information”. The following will describe an operation of the setting function 37e when the diagnosis information indicates “atrioventricular block”, referring to
In the example of
The setting function 37e further sets a reconstruction timing RT2 to reconstruct image data of the subject P during the X-rays irradiation period under the set scan condition.
Next, an example that the diagnosis information obtained by the second obtaining function 37d indicates “atrial fibrillation” is described. In this case the setting function 37e identifies a scan condition and a reconstruction condition associated with the diagnosis information “atrial fibrillation”, referring to the examination-condition database 351 in the storage circuitry 35. In the example of
The setting function 37e then sets a scan condition based on “prepare free area for data acquisition for several seconds . . . ” in accordance with the measurement information obtained by the second obtaining function 37d. Likewise, the setting function 37e sets a reconstruction condition based on “reconstruct rear end of 250 ms data”. The following will describe an operation of the setting function 37e when the diagnosis information indicates “atrial fibrillation” referring to
In the example of
Upon detecting RS7 in
The setting function 37e starts counting the time from the start of X-ray irradiation and sets a time count of 250 ms as an irradiation end time EE3. In other words, the setting function 37e sets a scan timing ST3. When detecting a next R wave before a lapse of 250 ms from the irradiation start time ES3, the system control function 37a discontinues the X-ray irradiation and the setting function 37e resets the time count from the start of X-ray irradiation.
If no next R wave is detected after a lapse of 250 ms, the system control function 37a may continue the X-ray irradiation for more than the period of 250 ms. In this case the setting function 37e may set the time at which a next R wave rising (RS8 in
The setting function 37e also sets a reconstruction timing RT3 to reconstruct image data of the subject P during the X-ray irradiation period according to the set scan condition. When the subject P has undergone the X-ray irradiation for more than 250 ms, the setting function 37e may determine, as the reconstruction timing, a period from a time 250 ms before the irradiation end time EE3 to the irradiation end time EE3.
Next, an example that the diagnosis information obtained by the second obtaining function 37d indicates “ventricular premature contraction (bigeminy)” is described. In this case the setting function 37e identifies a scan condition and a reconstruction condition associated with the diagnosis information “ventricular premature contraction (bigeminy)”, referring to the examination-condition database 351 in the storage circuitry 35. In the example of
The setting function 37e then sets a scan condition based on “aim to scan second half of longer RR” in accordance with the measurement information obtained by the second obtaining function 37d. Likewise, the setting function 37e sets a reconstruction condition based on “reconstruct second half of longer RR”. The following will describe an operation of the setting function 37e when the diagnosis information indicates “ventricular premature contraction (bigeminy)”, referring to
Duration RR3 represents a length of time from the point RP3 to the point RP4 and a shorter RR interval. Duration RR4 represents a length of time from the point RP4 to the point RP5 and a longer RR interval. Duration RR5 represents a length of time from the point RP5 to the point RP6 and a shorter RR interval.
In the example of
Upon detecting the findings NP and BW from the waveform from the point RP5 to the point RP6, the setting function 37e sets a scan timing in a second half of the RR interval on the premise that an RR interval between the point RP6 and a next R-wave peak (expected point RP7) is equal to the duration RR4.
As an example, the setting function 37e starts counting the time from the time at which a peak of the wide QRS wave (point RP6 in
The setting function 37e determines the time corresponding to the point PS2 as an irradiation end time EE4. The point PS2 is detected from the waveform from the point RP4 to the point RP5 in the RR interval between the point RP6 to the next R-wave peak. In other words, the setting function 37e sets a scan timing ST4. The setting function 37e also determines a duration from the time 250 ms before the irradiation end time EE4 to the irradiation end time EE4 as a reconstruction timing RT4. When the irradiation time is less than 250 ms, scanning of the subject P is iterated until a lapse of 250 ms.
The setting function 37e may predict a next P-wave rising time based on a longer RR interval of the previous electrocardiogram from which bigeminy of the subject P was detected, and set the predicted time as an irradiation end time and a time 250 ms before the irradiation end time as an irradiation start time. Further, when the measurement information includes the frequency of irregular pulse being less than a threshold, the setting function 37e may consider the subject P as having equal pulse and set a suitable examination condition for the subject P.
The above embodiments have described several examples of the examination condition setting for illustrative purpose, but it is not intended to limit the examination condition setting to such examples.
Now, processing to be performed by the X-ray CT apparatus 1 of one embodiment will be explained.
First, the first obtaining function 37c obtains electrocardiogram waveforms (step S101). For example, the first obtaining function 37c obtains electrocardiogram waveform data as transmitted from the electrocardiograph 40 in real time. The second obtaining function 37d then obtains analysis information (step S102). For example, the second obtaining function 37d obtains diagnosis information and measurement information resulting from analyzing the electrocardiogram waveforms transmitted from the electrocardiograph 40.
The setting function 37e sets a scan condition (step S103). For example, the setting function 37e identifies a scan condition associated with the diagnosis information obtained at step S102, with reference to the examination-condition database 351 in the storage circuitry 35. The setting function 37e also sets a scan timing and an operation condition for the respective elements of the X-ray CT apparatus 1 according to the scan condition, based on the measurement information obtained at step S102.
The setting function 37e sets a reconstruction condition (step S104). For example, the setting function 37e identifies a reconstruction condition associated with the diagnosis information obtained at step S102, with reference to the examination-condition database 351 in the storage circuitry 35. The setting function 37e also sets a reconstruction timing according to the reconstruction condition, based on the measurement information obtained at step S102.
Next, the system control function 37a controls the respective elements of the X-ray CT apparatus 1 to perform a scan of the subject P (step S105). For example, the system control function 37a controls the scan control circuitry 33 under the scan condition set at step S103. Under the control of the system control function 37a, the scan control circuitry 33 performs control over the operations of the gantry 10 and the couch driver 21 to irradiate the subject P with X-rays.
The system control function 37a reconstructs X-ray CT image data (step S106), completing the processing. For example, the system control function 37a controls the image reconstruction circuitry 36 according to the reconstruction condition set at step S104. The image reconstruction circuitry 36 reconstructs X-ray CT image data resulting from scanning the subject P at step S105, to generate image data.
The X-ray CT apparatus 1 according to the present embodiment described above obtains the electrocardiogram waveforms of the subject P acquired by the electrocardiograph 40, obtains the analysis information resulting from analyzing the electrocardiogram waveforms, and sets an examination condition based on the electrocardiogram waveforms and the analysis information.
In this manner, for example, the X-ray CT apparatus 1 can automatically set the scan condition and the reconstruction condition in accordance with the diagnosis information by simply obtaining the electrocardiogram waveforms, the measurement information, and the diagnosis information. In addition, the diagnosis information reflects the clinical state of the subject P. Namely, the X-ray CT apparatus 1 of one embodiment can set the scan condition and the reconstruction condition depending on the clinical state of the subject P. As such, the X-ray CT apparatus 1 can allow healthcare professionals such as a radiology technician to easily set a suitable scan condition and reconstruction condition for X-ray CT examination of the subject P depending on the clinical state of the subject P even if they are not familiar with clinical states related to the circulatory organs.
In addition, the X-ray CT apparatus 1 of the present embodiment may obtain the analysis information with a delay from the obtainment of the electrocardiogram waveforms. For example, the diagnosis information and the measurement information included in the analysis information are unlikely to largely change in a short period of time. Thus, the examination condition setting based on the analysis information is feasible even with a delay in obtaining the analysis information.
The above-described embodiments are implementable in modified form by partly changing the elements or functions of the X-ray CT apparatus 1, when appropriate. In this regard, exemplary modifications of the embodiments are presented below. The following will mainly describe different features from the embodiments and omit describing the same or similar features in detail. The modifications presented below may be implemented individually or in combination when appropriate.
First Modification The above embodiments have described an example that the X-ray CT apparatus 1 obtains diagnosis information and measurement information from the electrocardiograph 40. In a first modification the X-ray CT apparatus 1 analyzes electrocardiogram waveforms by itself to obtain diagnosis information and measurement information.
According to the first modification, the second obtaining function 37d obtains analysis information based on the electrocardiogram waveforms obtained by the first obtaining function 37c. For example, the second obtaining function 37d analyzes the electrocardiogram waveforms obtained by the first obtaining function 37c to obtain diagnosis information and measurement information. The second obtaining function 37d may obtain either of the diagnosis information and the measurement information. The means to analyze the electrocardiogram waveforms is not limited to a particular means and any of a variety of known analyzing techniques is adoptable.
According to the first modification, the electrocardiograph 40 performs no analysis of electrocardiogram waveforms. This can lead to simplifying the electrocardiograph 40 in structure and configuration in the first modification.
The first modification has described an example that the X-ray CT apparatus 1 analyzes the electrocardiogram waveforms. In a second modification, for example, the analysis information is obtained from an exterior apparatus.
According to the second modification, the second obtaining function 37d obtains analysis information from an exterior apparatus. For instance, the second obtaining function 37d obtains diagnosis information and measurement information as a result of the most recent electrocardiographic test from a server such as an electronic medical record server. As an example, in response to an operator's instruction to obtain diagnosis information and measurement information via the input circuitry 31 of the console 30, the second obtaining function 37d obtains diagnosis information and measurement information as a result of the most recent electrocardiographic test.
Alternatively, the second obtaining function 37d may obtain analysis information directly input via the console 30. For example, the analysis information may be recorded on a computer-readable recording medium such as a flexible disk (FD), a CD-ROM, a magneto-optical disk (MOD), or a digital versatile disk (DVD). In such a case the second obtaining function 37d may read and obtain analysis information from the recording medium using a recording-medium reader (not illustrated) connected to the console 30.
In the second modification, the second obtaining function 37d of the X-ray CT apparatus 1 no longer performs the analysis process. Thus, the second modification makes it possible to lessen the processing load on the processing circuitry 37 of the X-ray CT apparatus 1.
In the embodiments and modifications as above, the biological monitor is exemplified by the electrocardiograph. The biological monitor is not limited to the electrocardiograph and may be, for example, a respiration detector 50.
The respiration detector 50 includes a respiration sensor to obtain respiratory waveforms of the subject P. The respiration sensor includes, for example, a laser generator and a light receiver. The respiration sensor processes a reflected optical signal by the abdominal surface of the subject P to obtain a length of time from laser irradiation to reception of reflected light or phase variations in the reflected optical signal. The respiration sensor iteratively computes the distance between the laser generator and the abdominal surface of the subject P in real time based on the time or phase variations.
In the third modification the respiration detector 50 includes a laser generator and a light receiver by way of example, however, the respiration detector 50 is not limited to such an example. As an example, the respiration detector 50 may include a band and a pressure sensor. The band is attached to the abdominal region of the subject P and the pressure sensor is attached to a location in-between the band and the abdominal region to observe a respiratory state of the subject P from variations in pressure. For another example, the respiration detector 50 may include an optical reflective member and a camera. The optical reflective member may be attached to a material placed on the abdominal region and be captured by the camera, to observe a respiratory state of the subject P by tracking the motion of the optical reflective member.
The respiration detector 50 obtains and transmits the respiratory waveforms to the console 30. The console 30 stores the respiratory waveforms in the storage circuitry 35 upon receipt. Thus, the storage circuitry 35 stores therein the respiratory waveforms. A duration of one cycle of respiratory waveforms is normalized to zero to 100%, and each position in the duration represented by % is referred to as a respiratory phase. For example, in the respiratory phase, a duration from a maximal inspiration to a next maximal inspiration is normalized to zero to 100%.
Further, the respiration detector 50 obtains analysis information by analyzing the respiratory waveforms of the subject P and transmits it to the console 30. The console 30 stores the analysis information in the storage circuitry 35 upon receipt from the respiration detector 50.
According to the third modification, the scan control circuitry 33 performs respiratory-gated scanning under the control of the system control function 37a of the processing circuitry 37. The respiratory-gated scanning refers to performing scanning in a duration of a maximal inspiration being the peak of a respiratory waveform or a maximal expiration being the bottom of a respiratory waveform.
According to the third modification, the first obtaining function 37c of the processing circuitry 37 obtains respiratory waveforms of the subject P acquired by the respiration detector 50. For example, the first obtaining function 37c obtains respiratory waveforms of the subject P, as transmitted from the respiration detector 50 to the console 30 in real time.
The second obtaining function 37d obtains analysis information resulting from analyzing the respiratory waveforms of the subject P. For example, the second obtaining function 37d obtains measurement information representing a respiratory cycle, as transmitted from the respiration detector 50 to the console 30.
The setting function 37e sets an examination condition based on the respiratory waveforms obtained by the first obtaining function 37c and the measurement information obtained by the second obtaining function 37d.
Although not shown, the examination-condition database 351 in the storage circuitry 35 of the third modification contains respiratory cycle, delay time from a start of contrast injection to a scan start, scan time, and reconstruction timing in association with one another. The delay time and the scan time are examples of scan condition.
For example, the delay time and the scan time are associated with the respiratory cycle so as to allow scanning of the subject P to start and end at appropriate timing in the end-tidal phase in which the motion of the subject P diminishes. The reconstruction timing is associated with the respiratory cycle so as to reconstruct image data during a suitable duration in the end-tidal phase in which the motion of the subject P diminishes, for example.
For example, the setting function 37e identifies a delay time and a scan time associated with the respiratory cycle obtained by the second obtaining function 37d, referring to the examination-condition database 351. The setting function 37e sets a scan condition in accordance with the identified delay time and scan time. The setting function 37e further sets a reconstruction timing corresponding to the respiratory cycle obtained by the second obtaining function 37d, with reference to the examination-condition database 351.
In the third modification the X-ray CT apparatus 1 is connected to only the respiration detector 50, however, it may be connected to the respiration detector 50 and another biological monitor such as the electrocardiograph 40.
According to the third modification it is possible for the operator to set examination conditions of the X-ray CT apparatus 1 based on the analysis information obtained by analyzing the biological information from various biological monitors.
The embodiments and modifications have described the X-ray CT apparatus 1 as an example of image diagnosis apparatus but are not intended to limit the image diagnosis apparatus to the X-ray CT apparatus 1. Other examples of the image diagnosis apparatus include an image diagnosis apparatus for the circulatory organs (X-ray angiography apparatus) and a magnetic resonance imaging (MRI) apparatus.
For example, the MRI apparatus as the image diagnosis apparatus sets an imaging condition for ECG gated imaging based on the analysis information as to the electrocardiogram waveforms. In ECG gated imaging, MRI signals are acquired in synchronization with electrocardiogram waveforms.
According to the fourth modification, it is possible to allow the operator to easily set suitable examination conditions of various kinds of image diagnosis apparatuses according to the analysis information provided by the biological monitor.
The term “processor” used herein signifies circuitry such as a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), or a field programmable gate array (FPGA).
The processor can implement functions by retrieving and executing computer programs from storage circuitry. In place of being stored in the storage circuitry, the computer programs may be directly embedded in the circuitry of the processor. In this case the processor implements functions by retrieving and executing computer programs from its circuitry.
According to the embodiments, processors can be individually constituted as a single piece of circuitry, or a single processor can be constituted of a combination of multiple independent circuits to implement the respective functions. Alternatively, the elements shown in
The respective elements of the apparatuses and devices depicted in the figures of the above embodiments represent functional concepts and may not be physically structured as depicted. Namely, part or all of the apparatuses and devices can be distributed or integrated in any functional or physical unit depending on various loads or usage, in addition to the configurations shown in the figures.
The processing and functions performed by each of the apparatuses and devices can be entirely or partially implemented by a CPU or computer programs read and executed by the CPU or can be implemented as hardware by wired logic.
The control methods described in the embodiments can be implemented by execution of a prepared control program using a computer such as a personal computer or a workstation. Such a control program can be distributed via a network such as the Internet.
The control program can be recorded on a computer-readable recording medium such as a hard disk, FD, CD-ROM, MOD, or DVD and can be retrieved and executed from the recording medium by a computer.
According to at least one of the embodiments described above, it is made possible to easily set suitable examination conditions according to the analysis information provided from the biological monitor.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2023-138375 | Aug 2023 | JP | national |
