ObjectiveTo analyze intrahepatic vascular structures, divide liver segment automatically, and carry out virtual anatomic hepatectomy for virtual liver surgery planning based on liver threedimensional images. MethodsThe branches of portal vein were labeled in the level of segment based on spiral CT scanning images by using the liver surgery planning system software Liv 1.0. Thus, the simulation of an anatomical resection could be carried out. ResultsAccording to the portal segment branches, each individual liver segment could be divided automatically. The three-dimensional liver model was reconstructed based on liver segments, and the margin of liver segments was displayed clearly. On that basis, the simulation of anatomical resection and the volumetric estimation could be performed. ConclusionsThe three-dimensional liver model with intrahepatic vessel is reconstructed clearly, automatic segmentation of liver segment, the simulation of anatomical resection, and volumetric estimation can be applied in succession. The planning can be accomplished with Liv 1.0 on personal computer by the user, which provides a software platform for clinical application of virtual liver techniques.
ObjectiveTo investigate the effects of three-dimensional (3D) printed Ti6Al4V-4Cu alloy on inflammation and osteogenic gene expression in mouse bone marrow mesenchymal stem cells (BMSCs) and mouse mononuclear macrophage line RAW264.7.MethodsTi6Al4V and Ti6Al4V-4Cu alloys were prepared by selective laser melting, and the extracts of the two materials were prepared according to the biological evaluation standard of medical devices. The effects of two kinds of extracts on the proliferation of mouse BMSCs and mouse RAW264.7 cells were detected by cell counting kit 8 method. After co-cultured with mouse BMSCs for 3 days, the expression of osteogenesis- related genes [collagen type Ⅰ (Col-Ⅰ), alkaline phosphatase (ALP), Runx family transcription factor 2 (Runx-2), osteoprotegerin (OPG), and osteopontin (OPN)] were detected by real-time fluorescence quantitative PCR. After co-cultured with mouse RAW264.7 cells for 1 day, the expressions of inflammation-related genes [interleukin 4 (IL-4) and nitric oxide synthase 2 (iNOS)] were detected by real-time fluorescence quantitative PCR, and the supernatants of the two groups were collected to detect the secretion of vascular endothelial growth factor a (VEGF-a) and bone morphogenetic protein 2 (BMP-2) by ELISA. The osteogenic conditioned medium were prepared with the supernatants of the two groups and co-cultured with BMSCs for 3 days. The expressions of osteogenesis-related genes (Col-Ⅰ, ALP, Runx-2, OPG, and OPN) were detected by real-time fluorescence quantitative PCR.ResultsCompared with Ti6Al4V alloy extract, Ti6Al4V-4Cu alloy extract had no obvious effect on the proliferation of BMSCs and RAW264.7 cells, but it could promote the expression of OPG mRNA in BMSCs, reduce the expression of iNOS mRNA in RAW264.7 cells, and promote the expression of IL-4 mRNA. It could also promote the secretions of VEGF-a and BMP-2 in RAW264.7 cells. Ti6Al4V-4Cu osteogenic conditioned medium could promote the expressions of Col-Ⅰ, ALP, Runx-2, OPG, and OPN mRNAs in BMSCs. The differences were all significant (P<0.05).Conclusion3D printed Ti6Al4V-4Cu alloy can promote RAW264.7 cells to secret VEGF-a and BMP-2 by releasing copper ions, thus promoting osteogenesis through bone immune regulation, which lays a theoretical foundation for the application of metal prosthesis.
Objective To investigate the effects of in-vitro monolayer culture and three-dimensional (3-D) alginate microsphere culture on the differentiation of normal human nucleus pulposus cells (NPCs), and to discuss the regulatory mechanism of restoring the phenotype of dedifferentiated NPCs by culturing resveratrol (RES) in 3-D alginate microsphere. Methods Normal human nucleus pulposus tissues were harvested for culture and identification of NPCs from 6 patients with burst lumbar vertebra fracture. NPCs at passages 1, 3, 5, and 7 in the in-vitro monolayer culture were harvested to observe the morphology, cell aging, and proteoglycan expression. The cell proliferation rates of NPCs at passage 1 in-vitro in monolayer culture and in 3-D alginate microsphere culture were detected. NPCs at passage 7 were randomly divided into 3-D alginate microsphere control group (group A), RES group (group B), silent mating type information regulation 2 homolog 1 (SIRT1)- small interfering RNA (siRNA) + RES group (group C), and negative control-siRNA + RES group (group D); and NPCs in the in-vitro monolayer culture was monolayer control group (group E). After corresponding treatment, Western blot was used for determining the protein expressions of SIRT1, Aggrecan, and collagen type II; real-time fluorescence quantitative PCR was used for detecting SIRT1 mRNA expression. Results The cultured cells were identified to be NPCs. Morphological observation, senescence-associated β-galactosidase (SA-β-gal) staining, and toluidine blue staining showed that dedifferentiation of normal NPCs tended to occur under continuous in-vitro monolayer culture, which was more obvious with increase of passage number. NPCs in 3-D alginate microsphere culture showed significantly lower proliferation rate than NPCs in the in-vitro monolayer culture (P lt; 0.05), but it could significantly improve the protein expressions of collagen type II and Aggrecan in dedifferentiated NPCs, showing significantly difference between groups E and A (P lt; 0.05). The protein expressions of SIRT1, collagen type II, and Aggrecan in group B were significantly improved when compared with that in group A (P lt; 0.05). Real-time fluorescence quantitative PCR and Western blot showed that the expressions of SIRT1 mRNA and proteins in group C were significantly inhibited after transfected with SIRT1-siRNA when compared with those in groups B and D (P lt; 0.05), and the protein expressions of collagen type II and Aggrecan in group C were significantly lower than those in groups B and D (P lt; 0.05). Conclusion Continuous in-vitro monolayer culture could efficiently cultivate numerous seeding NPCs, but it is liable to dedifferentiate. In 3-D alginate microsphere culture, RES could restore the phenotype of dedifferentiated NPCs and synthesize more extracellular matrix, which is related to the regulation of SIRT1.
Objective To introduce the recent advances of the application of computer technology in tissue engineering. Methods The recent original articlesrelated to computer technology, medical image technology, computer-aided design, the advanced manufacture technology were summarized and systematically analyzed.Results Computer-aided tissue engineering is a new fieldon tissue engineering. It is the future direction of tissue engineering study. This article reviews recent development of medical CT/MRI scanning, three-dimensional reconstruction, anatomical modeling, computeraided design, computer-aided manufacturing, rapid prototyping， RP manufacturing of tissue engineering scaffolds and computeraided implantation.Conclusion Computer-aided tissue engineering can be used in scaffolds design and fabrication, computer-aided artificial tissue implantation. It is a new field on tissue engineering.
ObjectiveTo investigate the effectiveness of individual percutaneous cannulated screws fixation of computer-assisted design combined with three-dimensional (3D) guide plate by comparing with cast immobilization and open internal fixation for treatment of Herbert type Ib scaphoid fracture. MethodsBetween January 2010 and June 2015, 56 patients with fresh Herbert type Ib scaphoid fracture were treated with cast immobilization in 16 cases (external fixation group), with open reduction and internal fixation in 20 cases (open reduction group), and with individual percutaneous cannulated screws fixation of computer-assisted design combined 3D guide plate in 20 cases (minimal invasion group). There was no significant difference in gender, age, injury cause, side, disease duration, and classification of fractures between groups P>0.05).The time of bone union, bone nonunion rate, return-to-work time, wrist range of motion (ROM), and Mayo function score were recorded and compared. ResultsPrimary healing of incision was obtained in open reduction group and minimally invasion group, without related complications. The cases were followed up 10-24 months (mean, 16.6 months). The time of bone union and return-to-work time of minimal invasion group were significantly shorter than those of the other 2 groups (P<0.05), and the rate of bone nonunion was significantly lower than that of the other 2 groups (P<0.05). At last follow-up, the wrist ROM of minimal invasion group[(104.40±3.46)°] was significantly larger than that of external group[(94.20±2.42)°] and open reduction group[(96.40±2.66)°] (P<0.05). According to Mayo function score, the results were excellent in 6 cases, good in 5 cases, fair in 2 cases, and poor in 3 cases in external fixation group, with an excellent and good rate of 69%; the results were excellent in 9 cases, good in 7 cases, fair in 2 cases, and poor in 2 cases in open reduction group, with an excellent and good rate of 80%; the results were excellent in 16 cases, good in 3 cases, and fair in1 case in minimal invasion group, with an excellent and good rate of 95%; there was significant difference in excellent and good rate among groups (P<0.05). ConclusionIndividual percutaneous cannulated screws fixation of computer-assisted design combined with 3D guide plate has satisfactory effectiveness in the treatment of Herbert type Ib scaphoid fractures, with the advantages of mini-invasion, high accuracy, high rate of bone union, less complication, early return-to-work time.
ObjectiveTo explore the gait trajectory characteristics of patients after total knee arthroplasty (TKA) assisted by three-dimensional (3D) printing navigation template.MethodsTwenty female patients (20 knees) with knee osteoarthritis who were treated with TKA assisted by 3D printing navigation template between February 2017 and February 2018 were selected as the 3D printing group. The patients were 50-69 years old, with an average age of 57.2 years. The disease duration was 4-7 years, with an average of 5.6 years. The osteoarthritis was classified as Kellgren-Lawrence Ⅲ level in 5 cases and Ⅳ level in 15 cases. The preoperative hip-knee-ankle angle (HKA) was (170.8±5.6)°. All patients were varus deformity. According to age and affected side, 20 healthy female volunteers were selected as the control group. The volunteers were 51-70 years old, with an average age of 56.7 years. Preoperative HKA was (178.8±0.6)°. There was significant difference in HKA between the two groups (P>0.05). The HKA, Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and visual analogue scale (VAS) scores of the 3D printing group before and after operation were compared. At 6 months after operation, the gait trajectory characteristics of 3D printing group and control group were analyzed by Vicon gait capture system. The kinematics parameters included velocity, cadence, stride length, maximum knee flexion angle (stance), minimum knee flexion angle (stance), maximum knee flexion angle (swing), mean hip rotation angle (stance), mean ankle rotation angle (stance).ResultsThe incisions of 3D printing group healed by first intention, with no complications. All patients were followed up 7-12 months (mean, 9.0 months). The WOMAC and VAS scores at 6 months after operation were significant lower than those before operation (P<0.05). The HKA was (178.8±0.8)° at 4 weeks after operation and the difference was significant when compared with that before operation (t=39.203, P=0.000). The position of the prosthesis was good. The femoral posterior condyle osteotomy line, surgical transepicondylar axis, and patella transverse line were parallel, varus deformity was corrected, and lower limb alignment was restored to neutral position. Gait analysis at 6 months after operation showed that the differences in all kinematics parameters between the two groups were significant (P<0.05).ConclusionAssisted by 3D printing navigation template, TKA can alleviate pain symptoms and correct deformity, with satisfactory early effectiveness. Compared with healthy people, the early postoperative gait of the patients were characterized by decreasing velocity, cadence, stride length, knee flexion range, and increasing compensatory hip and ankle rotation range.
ObjectiveTo establish a model of three-dimensional (3-D) cephalometric analysis to study dentomaxillofacial deformities. MethodsBetween January 2012 and October 2013,15 patients with dentomaxillofacial deformities were treated using 3-D cephalometric analysis in orthognathic surgery plan.There were 7 males and 8 females with an average age of 23.6 years (range,17-37 years),including 4 cases of mandibular protrusion with maxillary deficiency,4 cases of maxillary protrusion with mandibular deficiency,2 cases of long face syndrome,and 5 cases of facial asymmetry.CT images were reconstructed by Mimics software.The anatomical landmarks were located,the reference planes and analysis planes were defined and the 3-D coordinate was established.The distance and degree between landmarks and analysis planes which defined in the measure project were measured. ResultsBased on the 3-D CT quantitative analysis methods,cephalometric analysis project was defined in the 3-D coordinate.3-D cephalometric analysis provided a convenient and precise method for the clinical measurement of dentomaxillofacial morphology,and reduce the time in preoperation analysis. ConclusionThe model of 3-D CT cephalometric analysis can provide precise information in the diagnosis and treatment planning of orthognathic surgery.
Objective To investigate and analyze the three-dimensional anatomic structure of glenoid bone in some Chinese people so as to provide the accurate anatomic data to design the new prosthesis of glenoid bone for Chinese people. Methods A total of 90 volunteers with two healthy shoulders (52 males and 38 females, aging 19-60 years with an average of 39.6 years) were selected. Five parameters were measured by use of three-dimensional computed tomography, volumerendering technique (VRT) and multiplanar reformation (MPR), including the maximum antero-posterior width (MAPW),antero-posterior radius of curvature (APROC), maximum supero-inferior height (MSIH), supero-inferior radius of curvature(SIROC) and version angle (VA) of glenoid. All parameters were measured two times, and the average values were analysed by SPSS13.0. The level of significance was set at P lt; 0.05. Results The average MAPW was (2.51 ± 0.32) cm, the average APROC was (5.50 ± 1.21) cm, the average MSIH was (3.45 ± 0.29) cm, the average SIROC was (3.98 ± 0.55) cm, and the average VA was (— 0.03 ± 4.66)°. There were no significant differences (P gt; 0.05) in MAPW, APROC, MSIH, SIROC and VA between two sides. There were significant differences (P lt; 0.05) in MAPW, MSIH, SIROC and VA, and no significant difference (P gt; 0.05) in APROC between female and male. MAPW was correlated with APROC, MAPW was correlated with MSIH, APROC was correlated with SIROC, and the correlation coefficient was 0.298, 0.495 and 0.262, respectively. Conclusion There are no significant differences in MAPW, APROC, MSIH, SIROC and VA of glenoid between two sides. There are sexual significant differences in MAPW, MSIH, SIROC and VA. The data and its statistical results may serve as guidel ines for the design of the glenoid component.
Objective To evaluate the directional significance of SurgiCase software in free fibula mandibular reconstruction. Methods Between September 2010 and March 2012, 10 patients with mandibular defect underwent free fibula mandibular reconstruction. There were 7 males and 3 females, with an age range of 19-43 years (mean, 27 years). The extent of lesions was 7 cm × 5 cm to 16 cm × 8 cm. In each case, three-dimensional spiral CT scan of the maxilla, mandible, and fibula was obtained before surgery. The CT data were imported into the SurgiCase software and the virtual surgery planning was performed. After that, the mandibular rapid prototyping was made according to customized design. The reconstruction surgery was then carried out using these preoperative data. During actual surgery, the extent of mandibular defect was from 6 cm × 3 cm to 16 cm × 5 cm; the length of fibula which was used to reconstruct mandible was 6-17 cm; and the area of flap was from 6 cm × 5 cm to 16 cm × 6 cm. Results Preoperative data could not be applied because the intraoperative size of tumor was larger than preoperative design in 1 case of mandibular ameloblastoma, and the fibula was shaped according to the actual osteotomy location; operations were performed successfully according to preoperative design in the other 9 patients. The operation time was 5-7 hours (mean, 6 hours). Primary healing of incision was obtained, without early complications. Ten patients were followed up 1 year. At last follow-up, 8 patients were satisfactory with the appearance and 2 patients complained with unsatisfied wide facial pattern. The panoramic radiograghs showed good bone healing. The range of mouth opening was 2.5-3.5 cm. Conclusion SurgiCase software can provide precise data for free fibula mandibular reconstruction during surgery. It can be applied widely in clinic.
Objective To investigate the cl inical directive significance of three-dimensional reconstruction of CT in treating mandibular angle hypertrophy. Methods Between March 2009 and January 2011, 18 patients with mandibular angle hypertrophy were treated using the three-dimensional reconstruction technology of CT. All patients were female, aged20-36 years with an average of 25 years. Eighteen patients included: 14 single mandibular angle hypertrophy, 3 mandibular angle hypertrophy with masseter hypertrophy, and 1 mandibular angle hypertrophy with bilateral asymmetry; 6 cases of ptosis of mandibular angle, 9 cases of prominent mandibular angle, and 3 cases of introversive mandibular angle. According to the types of mandibular angle hypertrophy, the surgical methods could be correctly chosen. The procedure was planned and simulated; the osteotomy l ine was marked and the osteotomy was measured on the workstations of three-dimensional reconstruction. Results No fracture of mandible occurred in the operation. Facial nerve temporary attack occurred in 1 case and recovered at 3 months after operation. All patients were followed up 6-12 months (mean, 7.6 months). After 6 months of operation, the effectiveness was satisfactory in 15 cases, basically satisfactory in 2 cases, and unsatisfactory in 1 case (bilateral asymmetry). Conclusion Based on three-dimensional reconstruction technology of CT, surgical design performed on the model will promote the accuracy of operation. Basically symmetrical appearances can be achieved with satisfactory results.