【Abstract】Objective To investigate the anatomic structure and experimental methods of peribiliary vascular plexus(PVP) in rat’s hepatic portal bile duct.Methods To observe the morphological structure of PVP in rat’s hepatic portal bile duct after the hepatic artery was perfused with Chinese ink and transparency management, performed and to make three dimensional reconstruction of PVP’s spacial structure in MoticBuaa3Dvol software.Results The microvascular distribution and plane structure of PVP in rat’s hepatic portal bile duct could be shown clearly through Chinese ink perfusion and transparency management. The three dimensional structure of PVP could be reconstructed effectively by MoticBuaa3Dvol software, its effect was verisimilitude. Conclusion Chinese ink perfusion and vitrification is a simple and easy method in PVP’s morphologic study of rat’s hepatic portal bile duct. MoticBuaa3Dvol software is useful in microvascular study of hepatic portal bile duct.
Objective To discussion the diagnostic significance of CT three dimension reconstruction in local recurrence after surgery for gastric cancer. Methods Thirty-nine patients with gastric cancer recurrence after radical surgery were performed multislice CT scan between December 2004 and December 2008 in The Third Affiliated Hospital of Harbin Medical University, and the images were reconstructed by three dimension reconstruction in workstation. The axial CT images and three dimension images of gastric cancer recurrence patients were diagnosed and compared. Results The detection rates of axial images and three dimensional CT images were 82.1% (23/28) and 100% (28/28) for pathological morphology, 62.5% (10/16) and 93.8%(15/16) for extension of tumors, 66.7% (10/15) and 93.3% (14/15) for lymph node metastasis, 87.5% (7/8) and 87.5% (7/8) for distant metastasis, respectively. Conclusions CT three dimension reconstruction can carry out more direct and solid results, such as measuring the vertical thickness of the thickened gastric wall, observing the infiltration situation with proximal organ, and metastasis of the lymph node. The method of three dimension reconstruction used for the diagnosis of local recurrence after surgery for gastric cancer is better than the axial image, and it can supply data which would be useful for the tumor advancing treatment.
Objective To explore and solve the key technologies of the three dimensional (3D) visual ization reconstruction of functional fascicular groups inside long segmented peri pheral nerve. Methods A 20 cm ulnar nerve from upper arm of fresh adult dead body was embedded by OCT with four pieces of woman’s hair which was used as locating material, then the samples were serially horizontally sl iced into 400 sl ices with 15 μm thickness and 0.5 mm interval. All sl iceswere stained with acetylcholinesterase (AchE) histochemical staining. After that, the 2D panorama images of the same sl ice were obtained with Olympus stereomicroscope and MSHOT MD90 micro figure image device before and after AchE staining. Using the layer processing technique of Photoshop image processing software, the recomposition images including complete 4 location pots were obtained, based on which the algorithm of optimized least square support vector machine (Optimized LS-SVM) and space transformation method was used to fulfill automatic registration. Finally, with artificial assistant outline obtaining, the 3D visual ization reconstruction model of functional fascicular groups of 20 cm ulnar nerve was made using Amira 4.1, and the effects of reverse reduction and the suitabil ity of 3D reconstruction software were evaluated. Results The two-time imaging technique based on the layer process of Photoshop image processing software had the advantages: the image outline had high goodness of fit; the locating pots of merging image was accurate; and the whole procedure was simple and fast. The algorithm of Optimized LS-SVM had high degree of accuracy, and the error rate was only 8.250%. The 3D reconstruction could display the changes of the chiastopic fusion of different nerve functional fascicular groups directly. It could extract alone, merge and combine arbitrarily, and revolve at any angles. Furthermore, the reverse reduction on arbitrarily level dissection of the 3D model was very accurately. Conclusion Based on the two-time imaging technique and computer image layer processing technology, the compute algorithm of auto-registration can be developed and appl ied to 3D visual ization reconstruction of long segmented peripheral nerve. The technological processes is fast, and the reconstruction effect is good.
ObjectiveTo study the digital anatomy and application value of the thoracic dorsal artery based on CT angiography (CTA). MethodsBetween September 2012 and June 2014, aorta CTA images were chosen from 10 cases (20 sides) undergoing aorta CTA. By using Mimics 17.0 software for three dimensional (3D) reconstruction of image post-processing, the digital vascular anatomical information were obtained after observing and measuring the origin of the thoracic dorsal artery, the number of perforators, type, inner diameter, and pedicle length; and the body surface location of perforator vessel was determined, and then the thoracic dorsal artery perforators tissue flap harvesting was simulated. Results3D reconstruction images showed that the thoracic dorsal artery originated from subscapular artery, 76 perforator vessels were found, including 32 perforators (42.1%) from the medial branch of the thoracic dorsal artery and 44 perforators (57.9%) from the lateral branch of the thoracic dorsal artery, of which 69 were intramuscular perforators (90.8%) and 7 were direct skin artery (9.2%). The inner diameter of the thoracic dorsal artery was (1.69±0.23) mm, and its pedicle length was (2.12±0.64) cm. The first lateral perforator of the thoracic dorsal artery located at (1.65±0.42) cm above the horizontal line of the inferior angle of scapula and at (1.68±0.31) cm lateral to vertical line of the inferior angle of scapula. The first medial perforator located at (1.43 ±0.28) cm above the horizontal line of the inferior angle of scapula and at (1.41±0.28) cm lateral to vertical line of the inferior angle of scapula. The thoracic dorsal artery perforators flap harvesting was successfully simulated. ConclusionCTA is a more intuitive method to study the thoracic dorsal artery in vivo, it can clearly display 3D information of the main blood supply artery course and distribution after flap reconstruction, so it can effectively and accurately guide the design of the flap.
ObjectiveTo evaluate the ectopic osteogenesis of recombinant human bone morphogenetic protein 2 (rhBMP-2) loaded chitosan (CS)/dextran sulfate (DS) by micro-CT. MethodsrhBMP-2/CS/DS microspheres were prepared by the ionic crosslinking and its shape was observed under the scanning electron microscope. The release of rhBMP-2 was determined from resultant microspheres by ELISA assay. Forty-eight Sprague Dawley male rats were randomly divided into 4 groups (n=12), quadriceps muscle bag model was made, gelatin sponge (group A), CS/DS microspheres (group B), rhBMP-2 (group C), and CS/DS/rhBMP-2 microspheres (group D) were implanted into the bags respectively. The tissue samples with heterotopic ossification were harvested for micro-CT scanning at 4, 8, 12, and 16 weeks. The tissue mineral density (TMD), bone volume fraction (BVF), trabecular thickness (Tb.Th), trabecular number (Tb.N), bone mineral density (BMD), and tissue mineral content (TMC) were measured. ResultsThe prepared rhBMP-2/CS/DS microspheres with smooth surfaces were spherical and evenly disperses without obvious agglomeration. At 2 hours, microsphere started a sudden release period in vitro; the release reached a peak at 2 days; and the release cycle lasted about 20 days. The rats survived to the end of the experiment. At each time point after operation, no radiation developed and no osteogenesis was observed by three dimensional reconstruction in groups A and B. However, radioactive strength and reconstructed bone tissue gradually increased in groups C and D, and group D had more radioautography and more bone tissues than group C. At each time point, TMD, BVF, Tb.Th, Tb.N, BMD, and TMC of groups A and B were zero. Ectopic bone formed with time, the other parameters showed an increasing trend except Tb.N in groups C and D, showing significant difference when compared with groups A and B at each time point (P < 0.05). There was no significant difference between groups C and D at 4 weeks (P>0.05); the parameters of group D were significantly higher than those of group C at 8-16 weeks (P < 0.05). ConclusionrhBMP-2/CS/DS microspheres have stronger ability of ectopic bone formation than single rhBMP-2.
Objective To establish a model for studying on mechanical responses of osteoblasts seeded in 3 dimensional(3D) scaffold. Methods Fifty pieces of bioderived cancellous bones, whose holes were 500 to 800 μm and density was 0.36 to 0.45g/cm3, were obtained as the scaffolds. They were cultured with the third passage suspension of Wistar rat. Twenty-four of the 50 scaffolds were constructed under apparent strain sine waveform with amplitude of 1 000 με, frequency of 3 Hz, and duration of 3 min/d, as experimental group. The other scaffolds were control group. After 3day coculture, osteoblasts were observed with scanning electron microscope. The proliferation of the osteoblasts was checked by MTT on scheduled date. Results Scanning electron microscopic observation showed that osteoblasts ttached and spread on the trabeculae, which presented the validity of the model under proper mechanical condition. Experiment showed that mechanical environment promoted theproliferation of osteoblasts. The observation of proliferation of osteoblasts showed that the quantity of osteoblasts in the experimental group was higher than that in the control group 1,4,8,12,16,20,24, and 28 days after culturing. Therewas significant difference between the two groups 12,16,20,24,and 28 days afterculturing(P＜0.05). Conclusion The establishment of the model can facilitate the study of mechanical responses of osteoblasts under different conditions.
Early screening based on computed tomography (CT) pulmonary nodule detection is an important means to reduce lung cancer mortality, and in recent years three dimensional convolutional neural network (3D CNN) has achieved success and continuous development in the field of lung nodule detection. We proposed a pulmonary nodule detection algorithm by using 3D CNN based on a multi-scale attention mechanism. Aiming at the characteristics of different sizes and shapes of lung nodules, we designed a multi-scale feature extraction module to extract the corresponding features of different scales. Through the attention module, the correlation information between the features was mined from both spatial and channel perspectives to strengthen the features. The extracted features entered into a pyramid-similar fusion mechanism, so that the features would contain both deep semantic information and shallow location information, which is more conducive to target positioning and bounding box regression. On representative LUNA16 datasets, compared with other advanced methods, this method significantly improved the detection sensitivity, which can provide theoretical reference for clinical medicine.
ObjectiveTo investigate the three-dimensional (3D) culture and morphology of human eccrine sweat gland cells. MethodsThe human eccrine sweat gland cells were isolated from normal abdominal full thickness skin by digestion of type II collagenase, and cultured in defined-keratinocyte serum free medium supplemented with 5 ng/mL recombinant human epidermal growth factor, 25 mg/mL bovine pituitary extract, 100 U/mL penicillin, and 100 μg/mL streptomycin at 37℃ in a humidified atmosphere of 5%CO2/95% air incubator. When the cell fusion reached above 80%, the cells were harvested and the concentration was adjusted to 1×105 cells/mL. The mixture of 0.3 mL cell suspension and 0.3 mL Matrigel basement-membrane matrix was cultured in 12-well plate. The cell growth was observed under an inverted phase contrast microscope. At 14 days after culture, frozen sections were prepared and were stained with HE to observe the cells morphology, and immunohistochemical analysis was used to detect the antigen expressions of cytokeratin 7 (CK7) and CK19. ResultsInverted phase contrast microscope observation showed that many free eccrine sweat gland tissues were seen after digestion of type II collagenase; eccrine sweat gland cells grew adhering to the wall at 3-5 days and continued division for 2-3 weeks to form single ring around the block sweat glands; cellular senescence were observed after 3-4 weeks. During the process of 3D culture, the single eccrine sweat gland cell divided into 2-4 cells after 2-3 days, and these cells subsequently formed small cell clusters, tubular-like structures and finally spheric-like shapes. After cultured for about 2 weeks, there was crack in part of the gelled mixture or liquefaction occurred. HE staining of frozen sections of the 3D cultures showed some of the tubular-like structures composed of 1-2 layers of epithelial cells, which were similar to the secretion part and the duct part of the eccrine sweat gland. Immunohistochemical analysis showed that CK7 and CK19 antigens expressed positively in the cells. ConclusionHuman eccrine sweat gland cells cultured in Matrigel can form the 3D structures which simulate the morphology of eccrine sweat glands in vivo.
ObjectiveTo study the difference of femoral condylar twist angle (CTA) measurement in three dimensional (3-D) reconstruction digital models of human knee joint based on the two dimensional (2-D) images of MRI and CT so as to provide a reference for selecting the best method of CTA measurement in preoperative design for the femoral prosthesis rotational position. MethodsThe CTA of 10 human cadaveric knee joint was measured in 3-D digital models based on MRI (group A), in 3-D digital models based on CT (group B), in the cadaveric knee joint with cartilage (group C), and in the cadaveric knee joint without cartilage (group D), respectively. The statistical analysis of the differences was made among the measurements of the CTA. ResultsThe CTA values measured in 3-D digital models were (6.43±0.53)° in group A and (3.31±1.07)° in group B, showing significant difference (t=10.235, P=0.000). The CTA values measured in the cadaveric knee joint were (5.21±1.28)° in group C and (3.33±1.12)° in group D, showing significant difference (t=5.770, P=0.000). There was significant difference in the CTA values between group B and group C (t=5.779, P=0.000), but no significant difference was found between group A and group C (t=3.219, P=0.110). ConclusionThe CTA values measured in the 3-D digital models based on MRI are closer to the actual values measured in the knee joint with cartilage, and benefit for preoperative plan.
ObjectiveTo evaluate the feasibility and accuracy of a novel three dimensional (3D) preoperative simulation software in a clinical setting for patients undergoing precise hepatectomy. MethodsThe clinical data of 85 patients with hepatocellular carcinoma underwent precise hepatectomy were retrospectively studied. All the patients received CT screening and subsequent evaluation on the liver resection volume and margin and the percentage of resected tumor by 3D preoperative simulation software, which compared with the actual resection liver values. The operation plan was optimized by virtual hepatectomy. ResultsThe liver, tumor as well as blood vessel could be clearly showed and reconstructed by 3D preoperative simulation software. All the patients underwent precise hepatectomy. After operation ascites occurred in 3 patients on 2 d, moderate pleural effusion occurred in 2 patients on 2 d, and bile leakage appeared in 4 patients on 5 d, which were improved by conservative treatment. The length of stay in all patients ranged from 6 to 88 d (mean 23 d), and no recurrence and death occurred within 30 d of operation. The predicted resection liver volume was significantly correlated with the actual resection volume (r=0.960, Plt;0.001), and the difference between the mean volume of predicted and actual resection liver was not significant (896.7 ml vs. 819.1 ml， t=1.851, P=0.068). In addition, the predicted resection margin was also correlated with the actual resection margin (r=0.972, Plt;0.001), with the difference in the mean resection margin was not significant too (12.2 mm vs. 11.9 mm， t=1.143, P=0.256). No patients suffered from severe postoperative complications. ConclusionsThe 3D preoperative simulation software is able to evaluate and simulate liver resection accurately, which may contribute to a safe precise hepatectomy plan.