Diffusion tensor imaging (DTI) is a rapid development technology in recent years of magnetic resonance imaging. The diffusion tensor interpolation is a very important procedure in DTI image processing. The traditional spectral quaternion interpolation method revises the direction of the interpolation tensor and can preserve tensors anisotropy, but the method does not revise the size of tensors. The present study puts forward an improved spectral quaternion interpolation method on the basis of traditional spectral quaternion interpolation. Firstly, we decomposed diffusion tensors with the direction of tensors being represented by quaternion. Then we revised the size and direction of the tensor respectively according to different situations. Finally, we acquired the tensor of interpolation point by calculating the weighted average. We compared the improved method with the spectral quaternion method and the Log-Euclidean method by the simulation data and the real data. The results showed that the improved method could not only keep the monotonicity of the fractional anisotropy (FA) and the determinant of tensors, but also preserve the tensor anisotropy at the same time. In conclusion, the improved method provides a kind of important interpolation method for diffusion tensor image processing.
Magnetic resonance imaging(MRI) can obtain multi-modal images with different contrast, which provides rich information for clinical diagnosis. However, some contrast images are not scanned or the quality of the acquired images cannot meet the diagnostic requirements due to the difficulty of patient's cooperation or the limitation of scanning conditions. Image synthesis techniques have become a method to compensate for such image deficiencies. In recent years, deep learning has been widely used in the field of MRI synthesis. In this paper, a synthesis network based on multi-modal fusion is proposed, which firstly uses a feature encoder to encode the features of multiple unimodal images separately, and then fuses the features of different modal images through a feature fusion module, and finally generates the target modal image. The similarity measure between the target image and the predicted image in the network is improved by introducing a dynamic weighted combined loss function based on the spatial domain and K-space domain. After experimental validation and quantitative comparison, the multi-modal fusion deep learning network proposed in this paper can effectively synthesize high-quality MRI fluid-attenuated inversion recovery (FLAIR) images. In summary, the method proposed in this paper can reduce MRI scanning time of the patient, as well as solve the clinical problem of missing FLAIR images or image quality that is difficult to meet diagnostic requirements.
rough the ultramicroscopic observation on muscle and microcirculation, Group A,where a largeamount of DXM combined with heporin was given svstematically and locally into the femoral artery of the severed limb before replantation, and in Group B only heporin was given, and Group C and D ascontrol.The results showed that if the hormone and heparin were administred in large dosage, it wasadvantageous to reduce the tissues from reperfusion injury during delayed replantation.
Complete three-dimensional (3D) tooth model provides essential information to assist orthodontists for diagnosis and treatment planning. Currently, 3D tooth model is mainly obtained by segmentation and reconstruction from dental computed tomography (CT) images. However, the accuracy of 3D tooth model reconstructed from dental CT images is low and not applicable for invisalign design. And another serious problem also occurs,i.e. frequentative dental CT scan during different intervals of orthodontic treatment often leads to radiation to the patients. Hence, this paper proposed a method to reconstruct tooth model based on fusion of dental CT images and laser-scanned images. A complete 3D tooth model was reconstructed with the registration and fusion between the root reconstructed from dental CT images and the crown reconstructed from laser-scanned images. The crown of the complete 3D tooth model reconstructed with the proposed method has higher accuracy. Moreover, in order to reconstruct complete 3D tooth model of each orthodontic treatment interval, only one pre-treatment CT scan is needed and in the orthodontic treatment process only the laser-scan is required. Therefore, radiation to the patients can be reduced significantly.
Objective To evaluate the phenomena of apoptosis and its relevant mechanism during ischemia-reperfusion period. Methods The published papers to explore the apoptotic phenomena and its mechanism in organs or tissues which experienced ischemia-reperfusion injury were reviewed. Results Apoptosis was common in ischemia-reperfusioned organ or tissue. The severity of apoptosis was influenced by many factors such as ischemia, hypoxia, oxygen free radials, intracellular free calcium ion overloading, various cytokines, et al; and also was regulated by bcl-2 family, caspase family and NF-κB，et al. Conclusion Apoptosis is a common phenomenum in ischemiareperfusioned organ or tissue which is affected and regulated by various factors.
Objective To summarize the application and progress of common autologous organ transplantation (AOT) techniques. Method A literature review and summary of previous and recent studies on common AOT was performed, including autologous liver transplantation, autologous kidney transplantation and intestinal autotransplantation techniques. Results AOT solved the issues of bleeding that cannot be controlled by in vivo resection of lesions, difficulties in vascular reconstruction, and the inability to radically resect lesions, and extended the indications for treatment of partially diseased conditions. Conclusions The AOT technique has an ameliorating effect on the tight donor situation in China, providing more potential donors. And the application of the AOT technique effectively avoids the usage of postoperative immunosuppressive drugs and the progression of lesions due to waiting for allogeneic organ transplantation. However, the clinical benefit in malignant tumors remains to be further investigated.
Objective To explore the feasibilities, methods, outcomes and indications of atlas pedicle screw system fixation and fusion for the treatment of upper cervical diseases. Methods From October 2004 to January 2006, 17 patients with upper cervical diseases were treated with atlas pedicle screw system fixation and fusion. There were 13 males and 4 females, ageing 19 to 52 years. Of 17 cases, there were 14 cases of atlantoaxial dislocation(including 3 cases of congenital odontoid disconnection，4 cases of old odontoid fracture，2 cases of new odontoid fracture(typeⅡC), 3 cases of rupture of the transverse ligament, and 2 cases of atlas fracture； 2 cases of tumor of C2; 1case of giant neurilemoma of C2,3 with instability after the resection oftumors. JOA score before operation was 8.3±3.0. Results The mean operative time and bleeding amount were 2.7 hours (2.1-3.4 hours) and 490 ml (300-750 ml) respectively. No injuries to the vertebral artery and spinal cord were observed. The medial-superior cortex of lateral mass was penetrated by 1 C1 screw approximately 3 mmwithout affecting occipito-atlantal motions. All patients were followed up 3-18 months. The clinical symptoms were improved in some extents and the screws were verified to be in a proper position, no breakage or loosening of screw and rob occurred. All patients achieved a solid bone fusion after 3-6 months. JOA score 3 months after operation was14.6±2.2. JOA improvement rates were 73%-91%(mean 82%). Conclusion The atlas pedicle screw system fixation and fusion is feasible for the treatment of upper cervical diseases and has betteroutcomes, wider indications if conducted properly.
Abstract: Objective To summarize the method and effective result of thoracoscopic intrapleural perfusion hyperthermochemotherapy(TIPHC) for treating malignant pleural effusion caused by lung cancer. Methods Fiftyeight patients with malignant pleural effusion caused by lung cancer were randomly divided into therapeutic group(30 cases) and control group(28 cases) between February 1999 and March 2005. Pleural biopsy and TIPHC under general ansthesia with unilateral ventilation were performed in the therapeutic group, and intrapleural injection of cisplatin was administered in control group after drainage of pleural effusion. The effect on malignant pleural effusion， the change for the concentration of carcinoembryonic antigen(CEA)， cytokeratin-19 fragments (CYFRA21-1)， neuronspecific enolase (NSE) and the side effect were compared before and after the treatment. Results The therapeutic group achieved total response rate of 100.0%, but only 53.6% in control group, with significant difference(χ 2=3.863, Plt;0.05). Furthermore, the concentration of CEA， CYFRA21-1， NSE in therapeutic group dramatically descended than control group(t=2.562,Plt;0.05). But there was no significant difference in side effect (Pgt;0.05). The pathological diagnosis of all the patients were determined in the therapeutic group. Conclusion TIPHC has the advantage of both diagnosis and treatment of malignant pleural effusions. It is safe and effective, and also able to determine the diagnosis. Furthermore, it offers the superiority of small wound， best visualization and convenient pleural biopsy.
To study the effect of intraperitoneal hyperthermic double distiled water and cis-diamminedichloro-platinum(DDP) perfusion to the peritoneal cancerous ascites,intraperitoneal injection of H22 cancer cells (2×107 tumor cell,each mouse) were performed in LACA mice. Five days after cancer cells injection, intraperitoneal perfusion of simple hypertherrnic (43℃) double distiled water(group Ⅰ) isotonic fluid (group Ⅱ ). DDP (group Ⅲ ), and hypertherrnic double distiles water perfusion combined with DDP (guoup Ⅳ ) were performed .The results showed that cancer cells in the peritoneal cavity of LACA mice were seriously damaged, the production of ascites was markedly inhibited and the survival days of LACA mice were prolonged in all groups . .The intraperitoneal hyperthermic double distilled water perfusion with DDP group showed more effective result as compared with the other groups,Only 1 peritoneal implanted dissemination was found after treatment in this group,Basing on the experimental from September 1991 through September 1993,intraperitoneal hyperthermic double distiled water perfusion with DDP was used to treat 32 advanced gastric cancer patients after radical gastrectomy with satisfactory results.
ObjectiveTo summarize the application of magnetic resonance imaging (MRI) in the evaluation of pancreatic exocrine function.MethodIn this paper, we reviewed and summarized the related literatures about the application of MRI in the field of pancreatic exocrine function evaluation in recent years.ResultsA variety of MRI techniques could be used to detect the pancreatic exocrine function. In addition to conventional MRI techniques, there were also MRI stimulated by pancreatic secretions, cine (dynamic) cholangiopancreatography based on space selective reverse recovery pulse, and so on.ConclusionThe new MRI techniques have potential for semi-quantitative and quantitative evaluation of pancreatic exocrine function.