A method for eliminating artifacts in medical CT scanners

Abstract

This invention relates to the field of medical CT scanner technology and provides a method for eliminating artifacts in medical CT scanners. The method includes: S1, placing the patient on the CT scanner bed, ensuring patient comfort and that the scanning area is within the scanner's field of view, and ensuring the patient is not carrying any metal objects that could affect or damage the CT scanner; S2, a monitoring module including a respiratory sensor, which collects the patient's respiratory signals, records and analyzes the signals, establishes a respiratory cycle through analysis, and outputs the respiratory cycle; S3, an analysis module obtains the respiratory cycle transmitted by the monitoring module, breaks down and processes the respiratory cycle, divides the respiratory cycle into multiple phases, and sends commands to the scanning equipment based on different phases. This device solves the problem of scanning artifacts caused by patient movement during CT scanning due to breathing. It achieves the goal of eliminating respiratory artifacts by monitoring breathing, changing the scanning strategy, and transmitting only the scanning results when the patient is stable.

Description

Technical Field

[0001] This invention relates to the field of medical CT scanner technology, and more specifically, to a method for eliminating artifacts in medical CT scanners. Background Technology

[0002] Medical CT scanners have a wide range of applications, and the diagnosis and treatment of many diseases rely heavily on them. However, the incidence of image artifacts in medical CT scans remains high. CT image artifacts reduce image quality, affecting radiologists' judgment and lowering the detection rate of lesions. Based on the causes of these artifacts, appropriate elimination measures should be taken to ensure the quality of CT images and provide a basis for disease diagnosis and treatment.

[0003] Currently, medical CT scanners on the market typically use full-spectrum X-rays. Full-spectrum X-rays utilize X-rays of different energies for imaging, thus enabling the differentiation of tissues of different densities. This technology provides clearer images, reduces the influence of overlapping structures, and improves diagnostic accuracy. However, in practical use, even with full-spectrum X-rays, the problem of poor image quality still exists. This poor image quality can easily lead to errors in the images seen by doctors, affecting their assessment of the patient's condition.

[0004] In the current situation, many factors can cause artifacts in medical CT images, such as foreign objects in the scanning area, uneven patient breathing, and software and hardware malfunctions. Generally speaking, although software and hardware malfunctions can be avoided through maintenance, uneven patient breathing or slight movements are difficult to avoid because patients are not trained and medical scanning can cause them to be nervous. Therefore, there is a need to develop a method to eliminate artifacts in medical CT images, so as to minimize the impact of artifacts on the doctor's feedback images, avoid affecting the doctor's judgment, and avoid affecting the medical outcome. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a medical CT artifact elimination method that avoids the influence of patient breathing on CT scans by monitoring the patient's breathing and avoiding body movement caused by the patient's breathing, thereby avoiding artifacts and obtaining more accurate CT images.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A method for eliminating artifacts in a medical CT scanner includes the following steps:

[0008] S1. Place the patient on the CT scanner bed, ensuring the patient is comfortable and the scanning area is within the scanner's field of view, and ensure the patient is not carrying any metal objects that could affect or damage the CT scanner;

[0009] S2. The monitoring module includes a respiratory sensor, which collects the patient's respiratory signals, records and analyzes the signals, establishes the respiratory cycle through analysis, and outputs the respiratory cycle.

[0010] S3. The analysis module obtains the respiratory cycle transmitted by the monitoring module, breaks down and processes the respiratory cycle, divides the respiratory cycle into multiple phases through the analysis module, and sends commands to the scanning device according to different phases.

[0011] S4. The scanning device performs scanning processing according to the instructions sent by the analysis module. The scanning device scans the affected area of ​​the patient. During the scanning process, the scanned information data is stored in the scanning module. The scanning module packages the data into a scan information package and transmits it to the preprocessing module. The scanning module clears the scan data it records.

[0012] The scanning device scans the patient by rotating and sending X-rays;

[0013] S5. The preprocessing module performs preprocessing steps on the scanned information packet and generates a preprocessed information packet.

[0014] S6. The reconstruction module reconstructs the processed information packet. Through multiple iterations, the reconstruction transforms the image into a precise three-dimensional image, generates a reconstruction information packet, and transmits the reconstruction information packet.

[0015] S7. The post-processing module performs post-processing on the reconstructed information packet, and obtains the total data packet after completion. The total data packet is then encrypted and stored.

[0016] By adopting the above technical solution and through reasonable settings of the scanning equipment, the scanning equipment continues to rotate and scan. This is because the time consumed by pausing and restarting the scanning equipment is much longer than the time of a human breath. If a pause method is used, the time interval will be too long, and the scanning will only continue after several sets of breathing cycles, which will greatly increase the scanning time. If the scanning time is too long, it will cause patient dissatisfaction and also consume additional power. However, by continuously scanning but pausing transmission, energy consumption can be reduced and patient comfort can be improved while ensuring the quality of the scanned images.

[0017] The present invention is further configured as follows:

[0018] The monitoring module establishes the respiratory cycle by placing a respiratory sensor in front of the patient's chest for monitoring. The respiratory sensor records the respiratory pressure in front of the patient's chest in real time.

[0019] The present invention is further configured as follows:

[0020] The respiratory sensor records the patient's chest pressure in real time. It establishes a pressure curve based on the patient's chest pressure, converts the pressure curve into a respiratory cycle, and a set of respiratory cycles corresponds to a set of pressure curve cycles. The respiratory cycles are then transmitted to the analysis module.

[0021] The present invention is further configured as follows:

[0022] The analysis module divides the respiratory cycle into multiple phases based on the pressure change curve. These phases include the expiratory phase, the inspiratory phase, and the steady phase.

[0023] Both the expiratory and inspiratory phases indicate changes in patient position and should not be monitored by scanning.

[0024] A steady phase indicates that the patient's position has not changed and should be monitored.

[0025] The present invention is further configured as follows:

[0026] If the analysis module determines that the patient is in the expiratory phase and in the inspiratory phase, it sends a pause command to the scanning device. The scanning device continues to rotate and scan, but the scanning device will not record the information scanned at this time.

[0027] If the analysis module determines that the patient is in a stable orientation, it sends a start command to the scanning device. The scanning device continues to rotate and scan, and records the information scanned at this time and imprints a timestamp.

[0028] By adopting the above technical solution, timestamp imprinting not only reveals the time and timing of each scan, but also allows for analysis of the patient's respiratory rate. Furthermore, analysis using timestamps can identify two possibilities if the timestamp intervals are excessively long: either the patient's respiratory rate is abnormal, or the CT scanner is malfunctioning. Through timestamp analysis, maintenance personnel can identify CT scanner malfunctions, or doctors can detect problems with the patient's respiratory rate.

[0029] The present invention is further configured as follows:

[0030] The preprocessing module performs preprocessing steps on the scanned information packets, the specific steps of which include:

[0031] Denoising is achieved by using a median filter to filter image noise.

[0032] Correcting image distortion and deformation;

[0033] Normalize the image pixel values.

[0034] The present invention is further configured as follows:

[0035] The specific steps of the reconstruction process in S6 are as follows:

[0036] S61. Set the initial image estimate and preset value. The initial image is set to a uniformly distributed initial image.

[0037] S62. Calculate the estimated projection data of the current image;

[0038] S63. Perform residual calculation to calculate the residual value between the projection data and the actual CT scan image;

[0039] S64. Update the image by updating the CT image based on the residual value information;

[0040] If the image is updated to the preset value, execute S65;

[0041] If the image value is lower than the preset value, execute S61;

[0042] S65, Output image.

[0043] The present invention is further configured as follows:

[0044] In S64, image updates are performed by updating the CT image based on the residual value information; wherein, each residual value update combines multiple projection data for image update.

[0045] The present invention is further configured as follows:

[0046] The specific steps of the post-processing in S7 are as follows:

[0047] S71. Improve the overall visibility of the image by increasing contrast and modifying image brightness;

[0048] S72. Segment and quantize the overall image; segmentation is performed based on the region of interest, and quantitative analysis is conducted, including volume measurement and density distribution.

[0049] The present invention is further configured as follows:

[0050] The total data packet is encrypted and stored using a symmetric key.

[0051] The master data package is uploaded to the hospital system, and a backup copy of the master data package is made to prevent data loss.

[0052] By adopting the above technical solution and using a symmetric key, the patient's total data packet is guaranteed not to be leaked, thus protecting patient privacy. At the same time, the backup data packet ensures that if the total data packet uploaded to the system is lost, the patient information can still be viewed through the backup data packet.

[0053] In summary, this application includes at least one of the following beneficial technical effects of the medical CT scanner artifact elimination method:

[0054] 1. By properly setting the scanning equipment, the scanning equipment continues to rotate and scan. This is because the time required for the scanning equipment to pause and restart is much longer than the time it takes for a human to breathe once. If a pause method is used, the time interval will be too long, and the scanning will only continue after several sets of breathing cycles, which will greatly increase the scanning time. If the scanning time is too long, it will cause patient dissatisfaction and also consume additional power. However, by continuously scanning but pausing the transmission, energy consumption can be reduced and patient comfort can be improved while ensuring the quality of the scanned images.

[0055] 2. Timestamps not only reveal the time and location of each scan, but also allow for analysis of the patient's respiratory rate. Furthermore, analysis of timestamps can reveal two possibilities: abnormal patient respiratory rate or CT machine malfunction. Timestamp analysis enables maintenance personnel to identify CT machine faults, or doctors to detect problems with the patient's respiratory rate.

[0056] 3. By using a symmetric key, the patient's total data packet is guaranteed not to be leaked, thus protecting patient privacy. At the same time, the backup of the total data packet ensures that if the total data packet uploaded to the system is lost, the patient information can still be viewed through the backup data packet. Attached Figure Description

[0057] Figure 1 This is a flowchart illustrating a method for eliminating artifacts in a medical CT scanner according to the present invention.

[0058] Figure 2 This is a schematic diagram of the breathing curve in this invention.

[0059] Figure 3 This is a flowchart of the encryption and decryption process in this invention. Detailed Implementation

[0060] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0061] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0062] Please see Figures 1-3 The present invention provides the following technical solutions:

[0063] Example 1, please refer to Figures 1-3 A method for eliminating artifacts in a medical CT scanner includes the following steps:

[0064] S1. Place the patient on the CT scanner bed, ensuring the patient is comfortable and the scanning area is within the scanner's field of view, and ensure the patient is not carrying any metal objects that could affect or damage the CT scanner;

[0065] S2. The monitoring module includes a respiratory sensor, which collects the patient's respiratory signals, records and analyzes the signals, establishes the respiratory cycle through analysis, and outputs the respiratory cycle.

[0066] S3. The analysis module obtains the respiratory cycle transmitted by the monitoring module, breaks down and processes the respiratory cycle, divides the respiratory cycle into multiple phases through the analysis module, and sends commands to the scanning device according to different phases.

[0067] S4. The scanning device performs scanning processing according to the instructions sent by the analysis module. The scanning device scans the affected area of ​​the patient. During the scanning process, the scanned information data is stored in the scanning module. The scanning module packages the data into a scan information package and transmits it to the preprocessing module. The scanning module clears the scan data it records.

[0068] The scanning device scans the patient by rotating and sending X-rays;

[0069] S5. The preprocessing module performs preprocessing steps on the scanned information packet and generates a preprocessed information packet.

[0070] S6. The reconstruction module reconstructs the processed information packet. Through multiple iterations, the reconstruction transforms the image into a precise three-dimensional image, generates a reconstruction information packet, and transmits the reconstruction information packet.

[0071] S7. The post-processing module performs post-processing on the reconstructed information packet, and obtains the total data packet after completion. The total data packet is then encrypted and stored.

[0072] Specifically, the monitoring module establishes the respiratory cycle by placing a respiratory sensor on the patient's chest. The sensor records real-time chest pressure; this is achieved by placing the sensor in an appropriate location on the chest, typically near the sternum or on either side of the pleural cavity. This location captures the expansion and contraction of the pleural cavity during respiration. The sensor is secured to the chest using tape, a chest strap, or other fixation devices to ensure it does not move during breathing. The sensor converts the captured pressure changes into electrical signals. These weak electrical signals are amplified using an amplifier and filtered to remove noise and interference.

[0073] The respiratory sensor records the patient's chest pressure in real time. It establishes a pressure curve based on the patient's chest pressure, converts the pressure curve into a respiratory cycle, and a set of respiratory cycles corresponds to a set of pressure curve cycles. The respiratory cycles are then transmitted to the analysis module.

[0074] Specifically, see Figure 2 The system analyzes the recorded signal waveforms to identify respiratory characteristics. Typical respiratory waveforms include peak values ​​for inspiration and expiration. By monitoring peak values, the system judges the peak values ​​for expiration and inspiration, as well as the smooth changes in the curve. The analysis module divides the respiratory cycle into multiple phases based on the pressure change curve, including the expiratory phase, the inspiratory phase, and the steady phase. The peak value for inspiration is set as the inspiratory phase, the peak value for expiration as the expiratory phase, and the rest as the steady phase.

[0075] It should be further explained that the expiratory and inspiratory phases both indicate changes in patient position and are not suitable for scanning monitoring. If the analysis module determines that the patient is in the expiratory or inspiratory phase, it sends a pause command to the scanning device. The scanning device continues to rotate and scan, but it does not record the information scanned at this time. It should be noted that the scanning device continues to rotate and scan because the time consumed by pausing and restarting the scanning device is much longer than the time of one human breath. If a pause method is used, the time interval will be too long, and the scanning will not continue until several sets of respiratory cycles, which will greatly increase the scanning time. If the scanning time is too long, it will cause patient dissatisfaction and also consume additional power. By continuously scanning but pausing transmission, energy consumption can be reduced and patient comfort can be improved while ensuring the quality of the scanned image.

[0076] A steady phase indicates that the patient's position has not changed and should be monitored. If the analysis module determines that the patient is in a steady phase, it sends a start command to the scanning device. The scanning device continues to rotate and scan, recording the scan information and imprinting a timestamp. It should be further noted that this timestamp not only indicates the time and timing of each scan but also allows for analysis of the patient's respiratory rate. Furthermore, analysis using the timestamps can reveal two possibilities: abnormal patient respiratory rate (due to anxiety or physical factors, which can be further assessed by a doctor) or CT machine malfunction. Analysis of the timestamps allows maintenance personnel to identify CT machine problems. If the patient's respiratory rate is inconsistent with the scanning frequency, it indicates a problem with the CT machine's scanning frequency or pressure sensor.

[0077] In this embodiment, it should be noted that the preprocessing module performs preprocessing steps on the scanned information packet, the specific steps of which include:

[0078] Denoising is achieved by using a median filter to filter image noise, thus preventing noise from affecting image quality. Image distortion and deformation are corrected by normalizing the image pixel values ​​to achieve the exact required pixel values.

[0079] In this embodiment, it should be noted that the specific steps of the reconstruction process in S6 are as follows:

[0080] S61. Set the initial image estimate and preset value. The initial image is set to a uniformly distributed initial image.

[0081] S62. Calculate the estimated projection data of the current image;

[0082] S63. Perform residual calculation to calculate the residual value between the projection data and the actual CT scan image;

[0083] S64. Perform image updates by updating the CT image based on the residual value information. Each residual value update combines multiple projection data for image updates, rather than updating based on a single projection data, to ensure that the preset value is reached more quickly and to improve image accuracy and image quality.

[0084] If the image is updated to the preset value, execute S65;

[0085] If the image value is lower than the preset value, execute S61;

[0086] S65, Output image.

[0087] It should be noted that the specific steps of the post-processing procedure in S7 are as follows:

[0088] S71. By increasing contrast and modifying image brightness, the overall visibility of the image is improved; this avoids poor image quality due to low brightness. Increasing image brightness can make things that are difficult to see in the image clearer, improve the accuracy of patient diagnosis, and avoid misdiagnosis caused by unclear images.

[0089] S72. Segment and quantify the overall image; segmentation is performed based on the region of interest, followed by quantitative analysis, including volume measurement and density distribution. By segmenting and quantifying the entire image, different organs and body parts of the patient can be displayed appropriately according to the patient's actual condition.

[0090] Specifically, see Figure 3 The master data packet is encrypted and stored using a symmetric key. It is uploaded to the hospital system, and a backup copy is created to prevent data loss. The symmetric key ensures the patient's master data packet is not leaked, protecting patient privacy. Furthermore, the backup ensures that if the uploaded master data packet is lost, the patient information can still be viewed through the backup.

[0091] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

Claims

1. A method for eliminating artifacts in a medical CT scanner, characterized in that, Includes the following steps: S1. Place the patient on the CT scanner bed, ensuring the patient is comfortable and the scanning area is within the field of view of the CT scanner. Ensure the patient is not carrying any metal objects that could affect or damage the CT scanner. S2. The monitoring module includes a respiratory sensor, which collects the patient's respiratory signals, records and analyzes the signals, establishes the respiratory cycle through analysis, and outputs the respiratory cycle. S3. The analysis module obtains the respiratory cycle transmitted by the monitoring module, breaks down and processes the respiratory cycle, divides the respiratory cycle into multiple phases through the analysis module, and sends commands to the CT scanner based on different phases. S4. According to the instructions sent by the analysis module, the CT scanner scans the affected area of ​​the patient. During the scanning process, the scanned information data is stored in the scanning module. The scanning module packages the data into a scan information packet and transmits it to the preprocessing module. The scanning module then clears the recorded scan data. Among them, the CT scanner scans the patient by rotating and sending X-rays; S5. The preprocessing module performs preprocessing steps on the scanned information packet to generate a preprocessed information packet. S6. The reconstruction module reconstructs the preprocessed information packet. The reconstruction is carried out through multiple iterations to reconstruct the image into a three-dimensional image, generate a reconstruction information packet, and transmit the reconstruction information packet. S7. The post-processing module performs post-processing on the reconstructed information packet after reconstruction, and obtains the total data packet after completion. The total data packet is then encrypted and stored. The respiratory cycle established by the monitoring module is monitored by placing a respiratory sensor in front of the patient's chest, and the respiratory sensor records the pressure in front of the patient's chest in real time. The respiratory sensor records the patient's chest pressure in real time. It establishes a pressure curve based on the patient's chest pressure, converts the pressure curve into a respiratory cycle, and a set of respiratory cycles corresponds to a set of pressure curve cycles. The respiratory cycles are then transmitted to the analysis module. The analysis module divides the respiratory cycle into multiple phases using the pressure curve, including the expiratory phase, the inspiratory phase, and the steady phase. Both the expiratory and inspiratory phases indicate changes in patient position and are not monitored by scanning. A steady phase indicates that the patient's position has not changed and should be monitored. If the analysis module determines that the patient is in the expiratory or inspiratory phase, it sends a pause command to the CT scanner. The CT scanner continues to rotate and scan, but does not record the information scanned at this time. If the analysis module determines that the patient is in a stable phase, it sends a start command to the CT scanner. The CT scanner continues to rotate and scan, and records the scanned information and timestamps it.

2. The method for eliminating artifacts in a medical CT scanner according to claim 1, characterized in that, The preprocessing module performs preprocessing steps on the scanned information packets, the specific steps of which include: Denoising is achieved by using a median filter to filter image noise. Correcting image distortion and deformation; Normalize the image pixel values.

3. The method for eliminating artifacts in a medical CT scanner according to claim 1, characterized in that, The specific steps of the post-processing in S7 are as follows: S71. Improve the overall visibility of the image by increasing contrast and modifying image brightness; S72. Segment and quantize the overall image; segmentation is performed based on the region of interest, and quantitative analysis is conducted, including volume measurement and density distribution.

4. The method for eliminating artifacts in a medical CT scanner according to claim 1, characterized in that: The total data packet is encrypted and stored using a symmetric key. The master data package is uploaded to the hospital system, and a backup copy of the master data package is made to prevent data loss.

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