1.Application of free-form deformation algorithm in fast three-dimensional bone reconstruction.
Xiangsen ZENG ; Hai ZHOU ; Chengtao WANG ; Dongmei WANG ; Gong CHEN
Journal of Biomedical Engineering 2014;31(5):1121-1126
This paper presents a unit free-form deformation (FFD) method applied to rapid three-dimensioanl (3D) bone reconstruction, which was based on traditional FFD. With the femur as an example, we reconstructed a 3D model of femur from two X-ray images and a standardized model by taking advantage of unit FFD algorithm. The X-ray images and its parameters were taken by C-arm device. Those parameters and X-ray contour are contributed to 3D reconstruction. The out contours of X-ray image and standard model were connected by point matching algorithm. The unit-FFD lattice was built to reconstruct standard model and finally made the contour of X-ray image and standard model exactly the same. Experiments on shape accuracy, robustness and time consuming, carried out by 35 specimen from cadaver, showed that mean error of shape (0. 52 mm) and mean construction time (112 s) were lower than those using traditional method (0.7-2.6 mm, 8-20 min). The method proposed in this paper shows a good prospect in clinical application and related research.
Algorithms
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Femur
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anatomy & histology
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diagnostic imaging
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Humans
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Imaging, Three-Dimensional
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Models, Anatomic
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Radiography
2.MRI diagnosis of reverse and separation of meniscus articular capsule
Xiaofeng TANG ; Chengtao ZHOU ; Renqi MU ; Guanghui ZHANG ; Yongzhong XU
Chinese Journal of Radiology 2001;0(02):-
Objective To explore the MR imaging of reverse and separation of meniscal articular capsule.Methods MR imaging of reverse and separation of meniscus articular capsule confirmed by surgery and arthroscope were analyzed retrospectively in 8 cases.Results The “Butterfly knot sign” disappeared and was replaced with fluid signal on the sagittal slice of meniscal body in 8 cases. Part of back angle remained in 3 cases. “Double anterior cruciate ligament sign” was showed on one side of middle sagittal slice in 7 cases. “Reverse meniscus sign” was revealed in intercondylar fossa on the coronary view in ~8 cases. Abnormal high signal was showed in the injured meniscus in 6 cases. Abnormal high signal was detected in the opposite meniscus in 5 cases.Conclusion The MR findings of reverse and separation of meniscus articular capsule include disappearance of “butterfly knot sign”, appearance of “reverse meniscus sign” and “double anterior cruciate ligament sign”. The diagnosis would be established if the former 2 signs were present or all the 3 signs were present simultaneously.
3.Study on the compression properties between articular cartilage and polyvinyl alcohol hydrogel as artificial cartilage
Feng LI ; Haiyu ZHOU ; Yonglin SU ; Chengtao WANG
Journal of Medical Biomechanics 2009;24(6):448-451,457
Objective To compare the compression properties of articular cartilage and polyinyl alcohol hydro-gel(PVA-H)as artificial carlage.Method Unconfined compression tests were conducted on articular card-lage and PVA-H,including stress-strain tests,creep tests and stress relaxation tests.The stress-strain rela-tionship of articular cartilage and PVA-H were measured.Result The compression modulus of articular card-lage was higher than that of PVA hydrogel.The average compression modulus of articular cartilage and PVA hydrogel was(3.6492±0.6199)Mpa and(1.5951±0.1469)Mpa,respectively.Condusions The experimental results revealed the differences existed between articular cartilage and PVA-H and this would be useful to fur-ther improve the mechanical properties of artificial cartilage.
4.Messenger RNA Profiling for Forensic Body Fluid Identifica-tion:Research and Applications
Zheng WANG ; Suhua ZHANG ; Di ZHOU ; Shumin ZHAO ; Chengtao LI
Journal of Forensic Medicine 2013;(5):368-374
Identifying the origin of body fluids left at a crime scene can give a significant insight into crime scene reconstruction by supporting a link betw een sample donors and actual criminal acts. How ev-er, the conventional body fluid identification methods are prone to various limitations, such as time con-sumption, intensive labor, nonparallel manner, varying degrees of sensitivity and limited specificity. Re-cently, the analysis of cell-specific messenger RNA expression (mRNA profiling) has been proposed to supplant conventional methods for body fluid identification. Since 2011, the collaborative exercises have been organized by the European DNA Profiling Group (EDNAP ) in order to evaluate the robustness and reproducibility of mRNA profiling for body fluid identification. The major advantages of mRNA profil-ing, compared to the conventional methods, include higher sensitivity, greater specificity, the ability of detecting several body fluids in one multiplex reaction, and compatibilitywith current DNA extraction and analysis procedure. In the current review ,we provided an overview of the present know ledge and detection methodologies of mRNA profiling for forensic body fluid identification and discussed its possi-ble practical application to forensic casew ork.
5.Imaging Diagnosis of Primary Malignant Fibrous Histiocytoma of Bone(A Report of 8 Cases)
Renqi MU ; Xiaofeng TANG ; Shouchang LAN ; Chengtao ZHOU ; Guanghui ZHANG
Journal of Practical Radiology 2001;0(10):-
Objective To analyze the imaging features and its value in diagnosing primary malignant fibrous histiocytoma(MFH) of bone.Methods Imaging features(X-ray,CT,MRI) in 8 cases of MFH confirmed pathologically,and were retrospectively reviewed.Results The location of lesions in 6 cases was in upper femur,2 cases was in upper tibilar.Worm-eaten-like bone destruction withindistinct margin was presented on X-ray film,some lesions showed slightly marginal sclerosis.Tumors were soft tissue density on CT(CT value was 34~35 HU).The masses of soft tissue were showed much distinct.Conclusion The primary MFH of bone is not of characteristic imaging findings.It can improve obviously the diagnosis of the disease by the comprehensive analysis of the imaging data.
6.MRI features of the intervertebral suppurative spondylitis
Xiaofeng TANG ; Youkuan REN ; Heng MA ; Chengtao ZHOU ; Renqi MU ; Xiaoyuan SUN
Chinese Journal of Radiology 2008;42(7):688-691
Objective To explore MRI findings of intervertebral suppurative spondylitis. Methods MRI findings of intervertebral suppurative spondylitis in 12 cases proved by surgery and 6 cases defined by clinical features were retrospectively analyzed. The MRI protocol included un-enhanced conventional scan in 18 cases and contrast-enhanced scan in 11 cases. Results Of the 18 cases, single focus was found in 16 cases, and multiple loci were seen in 2 cases. MRI findings included (1) Disappearance sign of nuclear crevice in 17 cases, accumulated fluid sign of intervertebral disc in 15 cases, intervertebral disc perforation in 4 cases, and intervertebral space narrowing in 7 cases. (2) Bone destruction under end plate and marrow oedema were shown in 18 cases, 17 cases had end plate destruction, 16 cases had covered sign of end plate.(3) Paraspinal soft tissue swelling was shown in 18 cases, in which thick wall microabscess was formed in 4 cases. (4) Vertebral canal was involved in 12 cases, vertebral canal abscess was formed in 5 cases.(5) Lump enhancement was demonstrated in 4 cases, nodular enhancement in 2, and ring-like enhancement in 2, respectively. No enhancement was seen in 3 cases. Dural sac linear enhancement was shown in 6 cases, and patchy enhancement in the anterior dural sac was shown in 10 cases. Conclusion Intervertebral suppurative spondytitis had characteristic MRI findings, and the key to correct diagnosis was to combine MRI finding with clinical characteristics.
7.A prognostic analysis of patients with pathologic complete response after preoperative neoadjuvant chemoradiotherapy for locally advanced rectal cancer
Haihua PENG ; Chengtao WANG ; Xin YU ; Kaiyun YOU ; Yufeng REN ; Zhifan ZENG ; Mengzhong LIU ; Tongchong ZHOU ; Yuanhong GAO ; Bixiu WEN
Chinese Journal of Radiation Oncology 2016;25(10):1079-1082
Objective To analyze the clinical factors for pathologic complete response ( pCR) after preoperative neoadjuvant chemoradiotherapy ( neo?CRT) for locally advanced rectal cancer. Methods From 2005 to 2012, 297 patients with locally advanced rectal cancer and complete clinical data were enrolled as subjects. Those patients were diagnosed with biopsy and treated with neo?CRT ( radiotherapy by 3?dimonsional conformal radiotherapy or volumetric?modulated arc therapy) followed by radical surgery. The logistic regression model was used for the multivariate analyses of the correlation of pCR with age, gender, distance between tumor and the anal verge, serum level of carcinoembryonic antigen ( CEA ) before treatment, hemoglobin level before treatment, cT staging, and cN staging. Results In all patients, 78 ( 26?7%) patients had pCR after treatment. The numbers of patients with pCR were 42( 34?4%) in patients with stage T1?T3 disease and 37(21?1%) in patients with stage T4 disease. In the patients with serum CEA levels no higher than 5?33 ng/ml, 55(36?4%) had pCR after treatment, while in the patients with serum CEA levels higher than 5?33 ng/ml, only 24( 16?4%) had pCR. The univariate analysis revealed that age, gender, distance between tumor and the anal verge, anemia before treatment, or cN staging were not related to pCR. The multivariate analysis showed that stage cT1?T3 and a serum CEA level no higher than 5?33 ng/ml before treatment were influencing factors for pCR after neo?CRT for locally advanced rectal cancer ( P=0?031,P=0?000) . Conclusions The clinical staging and the serum CEA level before treatment are influencing factors for pCR after neo?CRT for locally advanced rectal cancer. The serum CEA level before treatment can be considered as a predictor of pCR after neo?CRT for locally advanced rectal cancer.
8.Study on the 3D mathematical mode of the muscle groups applied to human mandible by a linear programming method.
Dongmei WANG ; Liniu YU ; Xianlian ZHOU ; Chengtao WANG
Journal of Biomedical Engineering 2004;21(1):85-88
Four types of 3D mathematical mode of the muscle groups applied to the human mandible have been developed. One is based on electromyography (EMG) and the others are based on linear programming with different objective function. Each model contains 26 muscle forces and two joint forces, allowing simulation of static bite forces and concomitant joint reaction forces for various bite point locations and mandibular positions. In this paper, the method of image processing to measure the position and direction of muscle forces according to 3D CAD model was built with CT data. Matlab optimization toolbox is applied to solve the three modes based on linear programming. Results show that the model with an objective function requiring a minimum sum of the tensions in the muscles is reasonable and agrees very well with the normal physiology activity.
Bite Force
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Computer Simulation
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Electromyography
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Humans
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Mandible
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physiology
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Programming, Linear
9.Radiographical diagnosis of posttraumatic knee joints hemarthrosis and lipohemarthrosis
Shuling LI ; Xulin LIU ; Qingju SUN ; Heng MA ; Guanghui ZHANG ; Chengtao ZHOU ; Xiaofeng TANG ; Wenle LI ; Zhongguang LIU ; Baozheng ZHANG
Chinese Journal of Radiology 2008;42(7):692-696
Objective To explore the imaging findings and diagnostic values of X-ray, CT, MR,and ultrasonography in traumatic knee joints hemarthrosis and lipohemarthrosis. Methods Traumatic knee joints hemarthrosis (12 knees) and lipohemarthrosis (18 knees) proved by operation (27 knees) or puncturation (3 knees) were included in the study. Horizontal-beam plain radiographs (16 knees), CT (30 knees), MRI (30 knees) and ultrasonography (24 knees) in supine position were investigated. Results (1)supine position horizontal-beam plain radiographs: Fat-liquid layer was found in 8 cases of lipohemarthrosis. Dense supragenual bursa was found in 1 case of lipohemarthrosis and 7 cases of hemarthrosis. Fracture (13 knees) was diagnosed correctly. (2) CT findings: double fluid-fluid layer was found in 11 of all 18 cases, and single fluid-fluid layer was found in 7 of 11 cases of lipohemarthrosis. Single fluid-fluid layer was found in 3 of 12 cases of hemarthrosis. Isodensity was detected in 9 cases, and high-density blood clot was found in 4 cases. Fracture (30 knees) was diagnosed correctly. (3) MRI findings: in 12 of 18 cases of lipohemarthrosis, double fluid-fluid layer was shown including supernatant layer as short T1, long T2signal and low signal after fat-suppression, middle layer as long T1, long T2 signal and high signal after fat-suppression, and dependent layer as iso-T1, iso-T2 and slight high signal after fat-suppression. Single fluid-fluid layer was seen in 6 cases, only had aforementioned upper and under layer.Only aforementioned supernatant layer and dependent layer were seen in 12 cases of hemarthrosis. 4 cases showed entire blood clot in fluid, T1WI showed middle signal or center iso-signal accompanied with peripheral high signal ring, and fat-suppression imaging showed high signal. T2WI and fat-suppressionimaging showed middling or high signal accompanied with peripheral low signal ring. Fracture (30 knees) was diagnosed correctly. (4) Ultrasound findings: In 10 of 14 cases of lipohemarthrosis, double fluid-fluid level was shown, supernatant layer as equal echo, middle layer as echoless, and dependent layer as cloudy echo. Four cases with single fluid-fluid level only showed aforementioned upper and under layer. Three of 10 cases of hemarthrosis showed single fluid-fluid level, only showing aforementioned upper and under layer,and 7 cases showed cloudy echo and float. In 3 cases the fluid blood clot showed irregular shape low-equal echo bolus. No fracture hne was found. Conclusions CT can clearly detect fracture line, hemarthrosis and lipohemarthresis, and can substitute plain radiography. MRI is the best way to diagnose hemarthresis and lipohemarthrosis. Ultrasonography can be used in diagnosing hemarthresis and lipohemarthrosis but not helpful in the diagnosis of fracture.
10.Research and analysis of failure data of contemporary artificial joint registration system.
Hai ZHOU ; Liao WANG ; Tianping YAO ; Chengtao WANG
Journal of Biomedical Engineering 2013;30(2):375-379
This paper is aimed to focus on the joint prosthesis failure event, to collect the statistic data about the failure of artificial joints issued by authoritative organizations at home and aboard, and to compare the functions of different types of the artificial joints. We generalized and compared current study analyzing the failure reason and type of joint prosthesis, and categorized the failure events according to the failure occurring time, i. e. short-term, medium-term and long-term. This paper could be helpful for improving and summarizing of artificial joint replacement surgery, and could put forward the requirements for the future artificial joints.
Arthroplasty, Replacement
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adverse effects
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statistics & numerical data
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Arthroplasty, Replacement, Hip
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adverse effects
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statistics & numerical data
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Arthroplasty, Replacement, Knee
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adverse effects
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statistics & numerical data
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Humans
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Joint Prosthesis
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Prosthesis Failure
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etiology