Four-dimensional cone beam CT (4D-CBCT) imaging can provide accurate location information of real-time breathing for imaging-guided radiotherapy. How to improve the accuracy of 4D-CBCT reconstruction image is a hot topic in current studies. PICCS algorithm performs remarkably in all 4D-CBCT reconstruction algorithms based on CS theory. The improved PICCS algorithm proposed in this paper improves the prior image on the basis of the traditional PICCS algorithm. According to the location information of each phase, the corresponding prior image is constructed, which completely eliminates the motion blur of the reconstructed image caused by the mismatch of the projection data. Meanwhile, the data fidelity model of the proposed method is consistent with the traditional PICCS algorithm. The experimental results showed that the reconstructed image using the proposed method had a clearer organization boundary compared with that of images reconstructed using the traditional PICCS algorithm. This proposed method significantly reduced the motion artifact and improved the image resolution.
Algorithms ; Cone-Beam Computed Tomography ; methods ; Four-Dimensional Computed Tomography ; Humans ; Image Processing, Computer-Assisted ; Organ Motion ; Radiographic Image Enhancement ; instrumentation ; methods ; Respiration

This paper introduces a kind of immune colloidal gold detector instrument from the aspects of machinery,hardware and software.The instrument first collects one image through a CMOS sensor and then analyzes the image with image processing algorithm on Linux platform.Firstly,the instrument sets and stores the parameters separately for each test item,and then calls the saved item parameters when testing the item sample.So,the instrument can be used in a variety of fields and items.In this paper,a quantitative experimental test on C-reactive protein sample was performed,and the results indicate the coefficient of determination what denoted equal to 0.99,and the repeatability is greater than 93%.
Algorithms ; Gold Colloid ; Image Processing, Computer-Assisted ; instrumentation

OBJECTIVE: To establish a cone beam computed tomography (ECBCT) system for high-resolution imaging of the extremities. METHODS: Based on three-dimensional X-Ray CT imaging and high-resolution flat plate detector technique, we constructed a physical model and a geometric model for ECBCT imaging, optimized the geometric calibration and image reconstruction methods, and established the scanner system. In the experiments, the pencil vase phantom, image quality (IQ) phantom and a swine feet were scanned using this imaging system to evaluate its effectiveness and stability. RESULTS: On the reconstructed image of the pencil vase phantom, the edges were well preserved with geometric calibrated parameters and no aliasing artifacts were observed. The reconstructed images of the IQ phantom showed a uniform distribution of the CT number, and the noise power spectra were stable in multiple scanning under the same condition. The reconstructed images of the swine feet had clearly displayed the bones with a good resolution. CONCLUSIONS The ECBCT system can be used for highresolution imaging of the extremities to provide important imaging information to assist in the diagnosis of bone diseases.
Algorithms ; Animals ; Artifacts ; Calibration ; Cone-Beam Computed Tomography ; instrumentation ; methods ; Equipment Design ; Extremities ; diagnostic imaging ; Image Processing, Computer-Assisted ; methods ; Phantoms, Imaging ; Radiographic Image Enhancement ; instrumentation ; methods ; Swine

OBJECTIVES: To develop a measurement software of lung compression degree to calculate the lung compression ratio in pneumothorax patients accurately and quickly, and then provide an objective assessment of damage degree in forensic clinical identification. METHODS: A volume calculation software was established according to the working principle of the CT instrument. CT data of 15 pneumothorax patients were selected as research objects. The lung compression ratio of pneumothorax patient was calculated by the lung compression volume calculation software of the CT instrument. Meanwhile, the lung compression ratio was also calculated by the developed volume calculation software. The lung compression ratio and operation time calculated by the two methods were analyzed statistically. Scatter plot graphs were draw based on related data, and the developed volume calculation software was verified. RESULTS: The difference between the lung compression ratios calculated by the two methods was not statistically significant, but showed a linear correlation （P<0.05）. The operation time of the developed volume calculation software was obviously shorter. CONCLUSIONS The volume calculation software developed in this study can calculate the lung compression degree of pneumothorax more conveniently and rapidly with easy accessibility, which shows an application value in the forensic practice.
Forensic Medicine/instrumentation* ; Humans ; Image Processing, Computer-Assisted/methods* ; Lung/diagnostic imaging* ; Pneumothorax ; Software ; Tomography, X-Ray Computed

Although pediatric pulmonary thromboembolism is historically believed to be rare with relatively little information available in the medical literature regarding its imaging evaluation, it is more common than previously thought. Thus, it is imperative for radiologists to be aware of the most recent advances in its imaging information, particularly multidetector computed tomography (MDCT), the imaging modality of choice in the pediatric population. The overarching goal of this article is to review the most recent updates on MDCT diagnosis of pediatric pulmonary thromboembolism.
Humans ; Image Processing, Computer-Assisted ; Multidetector Computed Tomography/instrumentation/*methods ; Pediatrics ; Pulmonary Embolism/physiopathology/*radiography ; Risk Factors

We retrospectively reviewed the thoracic CT scan protocols and technical parameters obtained from hospitals in Korea, one group during May 2007 (n = 100) and the other group during January 2012 (n = 173), before and after the establishment of the thoracic CT Guideline in 2008. Each group was also divided into two subgroups according to the health care delivery level, i.e. the "A" subgroup from primary and the "B" subgroup from secondary and tertiary care hospitals. When comparing the data from 2007 and 2012, the tube current decreased from 179.1 mAs to 137.2 mAs. The scan interval decreased from 6.4 mm to 4.8 mm. Also, the insufficient scan range decreased from 19.0% to 8.7%, and the suboptimal quality scans decreased from 33.0% to 5.2%. Between groups A and B, group B had lower tube voltages, smaller scan thicknesses, and smaller scan intervals. However, group B had more phase numbers. In terms of the suboptimal quality scans, a decrease was seen in both groups. In conclusion, during the five-year time period between 2007 and 2012, a reduction in the tube current values was seen. And the overall image quality improved over the same time period. We assume that these changes are attributed to the implementation of the thoracic CT guideline in 2008.
Asian Continental Ancestry Group ; Guidelines as Topic ; Hospitals ; Humans ; Image Processing, Computer-Assisted ; Radiation Dosage ; *Radiography, Thoracic ; Republic of Korea ; Retrospective Studies ; Societies, Scientific ; Surveys and Questionnaires ; *Tomography, X-Ray Computed/instrumentation

Traditional capsule image collects and transmits analog image, with weak anti-interference ability, low frame rate, low resolution. This paper presents a new digital image capsule, which collects and transmits digital image, with frame rate up to 30 frames/sec and pixels resolution of 400 x 400. The image is compressed in the capsule, and is transmitted to the outside of the capsule for decompression and interpolation. A new type of interpolation algorithm is proposed, which is based on the relationship between the image planes, to obtain higher quality colour images. capsule endoscopy, digital image, SCCB protocol, image interpolation
Algorithms ; Capsule Endoscopy ; instrumentation ; Equipment Design ; Image Processing, Computer-Assisted

OBJECTIVE: To assess whether multi-echo Dixon magnetic resonance (MR) imaging with simultaneous T2* estimation and correction yields more accurate fat-signal fraction (FF) measurement of the lumbar paravertebral muscles, in comparison with non-T2*-corrected two-echo Dixon or T2*-corrected three-echo Dixon, using the FF measurements from single-voxel MR spectroscopy as the reference standard. MATERIALS AND METHODS: Sixty patients with low back pain underwent MR imaging with a 1.5T scanner. FF mapping images automatically obtained using T2*-corrected Dixon technique with two (non-T2*-corrected), three, and six echoes, were compared with images from single-voxel MR spectroscopy at the paravertebral muscles on levels L4 through L5. FFs were measured directly by two radiologists, who independently drew the region of interest on the mapping images from the three sequences. RESULTS: A total of 117 spectroscopic measurements were performed either bilaterally (57 of 60 subjects) or unilaterally (3 of 60 subjects). The mean spectroscopic FF was 14.3 +/- 11.7% (range, 1.9-63.7%). Interobserver agreement was excellent between the two radiologists. Lin's concordance correlation between the spectroscopic findings and all the imaging-based FFs were statistically significant (p < 0.001). FFs obtained from the T2*-corrected six-echo Dixon sequences showed a significantly better concordance with the spectroscopic data, with its concordance correlation coefficient being 0.99 and 0.98 (p < 0.001), as compared with two- or three-echo methods. CONCLUSION: T2*-corrected six-echo Dixon sequence would be a better option than two- or three-echo methods for noninvasive quantification of lumbar muscle fat quantification.
Adult ; Aged ; Aged, 80 and over ; Female ; Humans ; Image Processing, Computer-Assisted ; Low Back Pain/*radiography ; Magnetic Resonance Imaging/instrumentation/*methods ; Male ; Middle Aged ; Muscles/radiography ; Spinal Cord

OBJECTIVETo explore the ideal screw entry point and optimal trajectory for anterior C1 lateral mass screw internal fixation, and provide an anatomical basis for the technique of anterior C1 lateral mass screw placement.

METHODSA radiographic analysis of the anatomy of the C1 lateral mass using Computed tomography, CT scan was performed in cervical spine of 56 healthy Chinese adults (28 males, 28 females; mean age, 36.5 years; age range, 18-55 years), by using the Mimics software to reconstruct the 3-D morphology of C1 lateral mass and measuring the inside, middle and outside effective height of the C1 lateral mass in front and back. Measuring the C1 lateral mass safe width with different extraversion angles range from 0° to 30° with a uniform interval of 5°, to find out the ideal extraversion angle. Measuring the range of sagittal angle, to find out the ideal sagittal angle.

RESULTSThe inside (H1), middle (H3) and outside (H5) effective height of the C1 lateral mass in front is 6.67 mm, 12.09 mm, and 17.51 mm, the inside (H2), middle (H4) and outside(H6) effective height of the C1 lateral mass in back is 8.17 mm, 13.20 mm, and 18.22 mm. When the extraversion angle choose 0°, 5°, 10°, 15°, 20°, 25°, 30°, and δ, the relative results of safe width (SW) of lateral mass were 4.73 mm, 5.36 mm, 5.90 mm, 6.33 mm, 6.44 mm, 5.70 mm, 4.38 mm, 6.95 mm averagely. The mean distance along the atlas anterior surface between the anterior tubercle and the screw entry point was 12.80 mm, the mean distance from the inferior border of the lateral mass to the screw entry point was 6.87 mm. The range of sagittal angle is 24.22° (-17.74°∼6.48°) .

CONCLUSIONSThe ideal extraversion angle was 21.14°. The mean distance along the atlas anterior surface between the anterior tubercle and the screw entry point was 12.80 mm. The mean distance from the inferior border of the lateral mass to the screw entry point was 6.87 mm. The ideal sagittal angle is -5.63°. These measurements may facilitate anterior C1 lateral mass screw fixation decreasing the risk of injury to the spinal cord, vertebral artery, and internal carotid artery theoretically. Delineating the individual anatomy in each case with CT scan before surgery is recommended.

Adolescent ; Adult ; Bone Screws ; Carotid Artery, Internal ; diagnostic imaging ; Cervical Atlas ; Cervical Vertebrae ; diagnostic imaging ; surgery ; Female ; Fracture Fixation, Internal ; instrumentation ; Humans ; Image Processing, Computer-Assisted ; Male ; Middle Aged ; Reconstructive Surgical Procedures ; Tomography, X-Ray Computed ; Vertebral Artery ; diagnostic imaging ; Young Adult

Magnetic induction method aims at the noninvasive detection of liver iron overload by measuring the hepatic magnetic susceptibility. To solve the difficulty that eddy current effects interfere with the measurement of magnetic susceptibility, we proposed an improved coil system based on the static field magnetization principle in this study. We used a direct current excitation to eliminate the eddy current effect, and a rotary receiver coil to get the induced voltage. The magnetic field for a cylindrical object due to the magnetization effect was calculated and the relative change of maximum induced voltage was derived. The correlation between magnetic susceptibility of object and maximum magnetic flux, maximum induced voltage and relative change of maximum induced voltage of the receiver coil were obtained by simulation experiments, and the results were compared with those of the theory calculation. The contrast shows that the simulation results fit the theory results well, which proves our method can eliminate the eddy current effect effectively.
Computer Simulation ; Humans ; Image Processing, Computer-Assisted ; Iron Overload ; diagnosis ; Liver ; physiopathology ; Magnetic Fields ; Magnetics ; instrumentation