Objective To improve the fitness and initial fixation strength between the hip and bone and to optimize the shape of the prosthetic implants. Methods The cross-section of hip canal was automatically extracted by Image processing. By using taper curve fit,hypocurve predigesting and the curve of shape center fit, the parameters of long-short diameter and the curve of shape center were got to design the hip shape.CAD was adopted to analyze and evaluate the configuration of bone and shape of hip.The “peg-in-hole” was employed to optimize the shape of implant by the visual test of “Drawingout” in computer. Results 23.2% hip-bone average matching rate and 0.033% bone damage rate were presented by CAD analysis. The implant extraction path were validated visually and quantitatively by measuring the maximum amount of overlap in the path configuration. Conclusion The valuable method for prothsetic hip design was presented by the way of image processing,graphics design and optimizingdesign in this study.
Objective To achieve threedimensional (3D) contour image of boneand articular cartilage for fabricating custommade artificial semiknee joint as segment bone allograft.Methods The distal femora of human and pig were scanned with Picker 6000 spiral X-ray computed tomography with 1.0 mm thick slice. The data obtained were treated in Voxel Q image workstation for 3D reconstruction with volume rendering technique. After being downloaded to personal computer at 0.1 mm interval, the transaxial 2D image data were converted into 2D digitized contour data by using image processing software developed by the team. The 2D digitized data were inputted into image processing software of Surfacer 9.0 (Imageware Company, USA), then the 3D wire frame and solidimages of femoral condyle were reconstructed. Subsequently， based on the clinical experience and the requirement of the design of artificial knee joint, the 3Dcontour image of bone or articular cartilage was extracted from the surrounding.Results The 3D contour image of bone or articular cartilage presented was edited and processed easily for the computer aided design(CAD) of custom-madeartificial knee joint.Conclusion The 3D contour image of boneand articular cartilage can be obtained by spiral CT scanning, and the digitized data can beapplied directly to CAD of custom-made artificial joint and subsequently rapidprototyping fabricating. In addition, the reconstruction method is simple and can be applied widely to clinical implant fabricating practice of dentistry and orthopaedics.
Objective To lay a foundation for study of optic narve damage in glaucoma by measuring the number and diameter of the optic nerve fibers and optic disc area in normal individuals. Methods The cross-sections of the optic nerve and the optic discs in 15 normal human eyes were examined with the use of a computerized image analysis system. Results The mean nerve fiber count was 10.08times;105plusmn;1.61times;105. The mean nerve fiber diameter was (0.99plusmn;0.04)mu;m. The nerve fiber count increased significantly with the increasing of cross-section area of the optic nerve, but the nerve fiber count was independent of the optic dise area. Conclusion This study provided anatomic basis for predicting the prognosis of optic nerve damage and further studyv of nerve damage in glaucoma. (Chin J Ocul Fundus Dis,1999,15:16-19)
Purpose To identify and quantitatively evaluate age-related changes in the retinal pigment epithelium (RPE) and underlying Bruch is membrane and choroid in donor human eyes. Methods 36unpaired human eyes of varying age (3-39 years) from Caucasian donors were supplied by Manchester Eye Bank (UK) or National Disease Research Interchange (Philadephia,USA).Modified Masson is trichrome staining was used to illustrate age-related changes in RPE cell, Bruch is membrane thickness, and density of choriocapillaries and thickness of the choroid. Data were assessed using computer-aided quantitative morphometric analysis method. ResultsThe thickness of Bruch is membrane increased with age while there is a change in morphology of RPE cells including a decrease in number and RPE cell thickening with age. RPE cells decreased at a rate of 8 cells/mm2 middot; year, RPE cell height and thickness of Bruch is membrane increased at rates of 0.01(mu;m/year) and 0.02 (mu;m/year) respectively. The luminal area of choriocapillaries and the thickness of choroid showed no close relation with age. Conclusion RPE cell loss and thickening of Bruch is membrane and RPE cells may be the earlier and primary alteration with age. (Chin J Ocul Fundus Dis,2000,16:236-239)
Purpose To investigate the pattern of subretinal neovascular membrane(SRNVM)in central exudative chorioretinitis(CEC). Methods With the help of a PC microcomputer,we performed a quantitative measurement of SRNVM in 32 eyes of 32 patients with Rieger is CEC. Results SRNVM-optic disc area ratio were 0.1151plusmn;0.0842．The foveola was on the top of SRNVM in 7 cases．The other 25 of SRNVMs were scattered in macular area around foveola,and 2 of them were nasal to it．The distance between the edge of SRNVM and foveola was less than 175mu;m in 13 cases,175～300mu;m in 4 cases and more than 300mu;m in 15 cases． Conclusion To be compared with the previous data,the present results suggested that laser photocoagulation might be one of the most important therapies for SRNVM in Rieger is CEC． (Chin J Ocul Fundus Dis,1998,14:114-115)
PURPOSE:To evaluated the luminal characteristics of the elderly central retinal vessels in the anterior optic nerves. METHODS:Serial sections of 15 central retinal arteries(CRA)and 23 central retinal veins (CRA)of 18 eyes of the aged 60 to 82 years old without anatomic malformation were examined by image analysis to investigate their luminal dimensional differences at the sites of lamina cribrosa and just anterior and posterior to it. RESULTS:The average values of the mean area of the CRA in the prelaminar,laminar,retrolaminar portions were separately(12.70,17.40,18.00)times;10-3mm2 and the mean perimetric length 0.56,0.56,0.57mm.No significant difference was detected in these three sites.The average values of the mean area of the CRV were respectively(7.00,5.40,7.90)）times;10-3mm2 and the mean perimetric length 0.44,0.38,0.41mm.There were marked differences between the prelaminar value and the laminar one,and between the laminar value and retrolaminar one by comparison. CONCLUSION:The CRA has a uniform radius from prelaminar to retrolaminar positions,and tube radius of the CRV at the level of the lamina cribrosa is the least. （Chin J Ocul Fundus Dis,1997,13: 213-214 ）
We searched and retrieved literature on the topic of medical image processing published on SCI journals in the past 10 years. We then imported the retrieved literature into TDA for data cleanup before data analysis and processing by EXCLE and UCINET to generate tables and figures that could indicate disciplinary correlation and research hotspots from the perspective of bibliometrics. The results indicated that people in Europe and USA were leading researchers on medical image processing with close international cooperation. Many disciplines contributed to the fast development of medical image processing with intense interdisciplinary researches. The papers that we found show recent research hotspots of the algorithm, system, model, image and segmentation in the field of medical image processing. Cluster analysis on key words of high frequency demonstrated complicated clustering relationship.
To solve the problems of noise interference and edge signal weakness for the existing medical image, we used two-dimensional wavelet transform to process medical images. Combined the directivity of the image edges and the correlation of the wavelet coefficients, we proposed a medical image processing algorithm based on wavelet characteristics and edge blur detection. This algorithm improved noise reduction capabilities and the edge effect due to wavelet transformation and edge blur detection. The experimental results showed that directional correlation improved edge based on wavelet transform fuzzy algorithm could effectively reduce the noise signal in the medical image and save the image edge signal. It has the advantage of the high-definition and de-noising ability.
A measurement system based on the image processing technology and developed by LabVIEW was designed to quickly obtain the range of motion (ROM) of spine. NI-Vision module was used to pre-process the original images and calculate the angles of marked needles in order to get ROM data. Six human cadaveric thoracic spine segments T7-T10 were selected to carry out 6 kinds of loads, including left/right lateral bending, flexion, extension, cis/counterclockwise torsion. The system was used to measure the ROM of segment T8-T9 under the loads from 1 N·m to 5 N·m. The experimental results showed that the system is able to measure the ROM of the spine accurately and quickly, which provides a simple and reliable tool for spine biomechanics investigators.