Application of the medical image three-dimensional visualization system of abdomen in diagnosis and evaluating resectability of pancreatic tumors / 中华外科杂志

<p><b>OBJECTIVE</b>To study the value and the clinical application of the Medical Image three-dimensional Visualization System of Abdomen (MI-3DVS) in diagnosis and evaluating resectability of pancreatic tumor.</p><p><b>METHODS</b>Twelve patients with pancreatic tumor were tested with 64-slice helical CT (64-MSCT) angiography, and the CT data was reconstructed with MI-3DVS from November 2008 to August 2009. The 3D findings were adopted in diagnosis and evaluating resectability, and the results were compared with surgical operation and the pathological finding. There were 7 male and 5 female, aged from 14 to 83 years. Within the 12 cases, there were 4 cases with pancreatic carcinoma, 5 cases with pancreatic solid pseudopapillary tumor, 2 cases with pancreatic serous cystadenoma, 1 case with pancreatic cyst (ductal epithelial papillary hyperplasia).</p><p><b>RESULTS</b>Nine tumors which had been regarded as removable pre-operatively with MI-3DVS were removed successfully. Three patients who were considered unresectable by other hospitals with CT were operated successfully with MI-3DVS. The other 3 patients' tumors were actually not able to be removed as pre-operative evaluation.</p><p><b>CONCLUSION</b>MI-3DVS plays an important role in diagnosis and assessment of resectability of pancreatic tumor.</p>

Study on visualized virtual surgery of living-related donor liver transplantation / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the significance of three dimensional visualization and virtual surgery system in living related donor liver transplantation surgery.</p><p><b>METHODS</b>Two patients suffered biliary calculi were scanned by 64 slice helical computer tomography (CT) on livers and the data were imported into medical image proceeding system (MIPS) for sequence. Man-made segmentation and true-up on the image from the data were carried out. Three dimensional (3D) models of the liver and the intrahepatic vessels were reconstructed by VTK software respectively. The models were exported with format STL from it and then were imported into the FreeForm Modeling System for smoothing and modifying. At last, living related donor liver transplantation were simulated with the force-feedback equipment (PHANToM).</p><p><b>RESULTS</b>It had great verisimilar image for the reconstructed 3D liver models with artery, hepatic vein, portal vein and bile duct. By seeing through liver, it had high fidelity and strong 3D effect for the intrahepatic artery, hepatic vein, portal vein and bile duct, and their spatial disposition and course and co-relationship were shown clearly. In the virtual surgery system, the virtual scalpel could be manipulated on 3D liver model with PHANToM. The simulating effect was the same as the clinic operation for living related donor liver transplantation.</p><p><b>CONCLUSIONS</b>The visualized liver model reconstructed is 3D and verisimilar, and it is helpful to design reasonable scheme for liver transplantation. It can improve the surgical effect, decrease the surgical risk, reduce the complication, enhance the communication between doctor and patient through designing surgical plan and demonstrating visualized operation before surgery.</p>

Establishment of a three-dimensional pancreas model for simulating surgical resection of pancreatic tail carcinoma using virtual-reality technique / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the feasibility of visual-reality technique for simulating surgical resection of pancreatic tail carcinoma using a 3-dimensional pancreas model reconstructed on the basis of the CT data.</p><p><b>METHODS</b>The original image data of 64-slice spiral CT was obtained from a patient with pancreatic tail carcinoma. Using adaptive region growing algorithm, the serial CT images were segmented and automatically extracted for 3-dimensional reconstruction of the pancreas and the anatomically related structures with a self-designed program. The model was then processed with Freeform Modeling System for image modification and smoothing. With the assistance of GHST SDK and PHANTOM software systems, preoperative simulation of surgical resection of the carcinoma was performed on the basis of the established pancreatic model.</p><p><b>RESULTS</b>The reconstructed 3-dimensional pancreatic model with the related structures clearly visualized the 3-dimensional structures of the pancreas, the pancreatic tail compromised by the carcinoma, and the adjacent organs, displaying also the distribution, courses and the anatomical relations of the ductal systems including the main pancreatic duct, abdominal aorta, portal vein system, and the biliary tract. During simulated surgery for pancreatic tail carcinoma resection, the GHOST SDK system allowed effective application of the virtual surgical instruments, and the use of PHANTOM software produced a surgical experience with high resemblance of that from an actual operation.</p><p><b>CONCLUSION</b>The serial CT data-based reconstruction of 3-dimensional pancreas model and simulated operation on this model using virtual-reality technique has great potentials for application in individualized surgical planning and surgical risk assessment in cases of pancreatic tail carcinoma, and also facilitates clinical training of the surgeons.</p>

Image segmentation and three-dimensional reconstruction of the liver based on 64-slice spiral CT scanning data / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the segmentation methods of the liver CT images and the value of 3-dimensional (3D) reconstruction of the liver in the planning of hepatic surgery.</p><p><b>METHODS</b>The 2D Digital Imaging and Communications in Medicine (DICOM) format data of the liver obtained from healthy volunteers were transformed into bmp format image, and the liver image segmentation was performed using Photoshop software. The 3D model was reconstructed using MIMICS software.</p><p><b>RESULTS</b>The DICOM format data of the liver obtained by 64 slice spiral CT included totally 658 slice images. The segmented liver image showed clear profiles and complete intrahepatic duct data were reserved. The segmented liver images were free of discontinuation during continuous observation. The liver surface and internal ductal system, including the hepatic arteries and veins, and the hepatic portal system and their branches, were represented clearly. The reconstructed liver allowed clear identification of the anatomic landmark and matched the actual liver volume. The reconstructed ductal structure were distinct and continuous with natural texture. The reconstructed liver and the hepatic internal duct system were simultaneously displayed by adjusting the transparency of the liver, and the blood vessels were also represented.</p><p><b>CONCLUSION</b>Segmentation of the liver images in different phases using Photoshop can be feasible for liver reconstruction. The reconstructed liver and the intrahepatic ductal structure allow vivid 3D observation of the spatial relationship among the major tracts and accurate estimation of the liver volume.</p>

Virtual surgery of cholecystotomy for calculus removal and cholecystectomy in patients with cholecystolithiasis / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the two-dimensional (2D) image segmentation, three-dimensional (3D) reconstruction and virtual surgery of cholecystectomy based on the 2D image data of the liver, biliary track and cholecystolithiasis obtained by 64-slice spiral CT.</p><p><b>METHODS</b>The image data of the liver, biliary track and cholecystolithiasis were obtained by 64-slice spiral CT scanning. Segmentation and automatic extraction of the images were performed using auto-adapting region growing algorithm. 3D reconstruction of the segmented data was carried out using MIMICS10.0 and self-designed software, and the data of the 3D model of the liver with the billiary tract were imported into FreeForm Modeling System for registration and smoothing. Virtual surgery of cholecystotomy for calculus removal and cholecystectomy were performed with Phantom.</p><p><b>RESULTS</b>The auto-adapting region growing algorithm allowed rapid image segmentation, and the 3D model of the liver based on the segmentation data clearly displayed vivid 3D structures of the liver. Virtual operations of cholecystectomy could be performed in the FreeForm Modeling System.</p><p><b>CONCLUSION</b>The algorithm we proposed can correctly and rapidly complete image segmentation and 3D reconstruction of cholecystolithiasis from the data 64-slice spiral CT, and allows virtual operations on the gallbladder.</p>

Clinical value of three-dimensional reconstruction of the biliary calculi based on 64-slice spiral CT scanning data / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the clinical value of 3-dimensional (3D) reconstruction of the liver and its ductal structures using 64-slice spiral CT data in hepatobiliary surgery.</p><p><b>METHODS</b>The image data of 64-slice spiral CT scanning was obtained from patients with biliary calculi. Image segmentation was performed both using computer programs and manually, and 3D reconstruction of the liver was carried out using Mimics software. The reconstructed model of the liver and the ductal system was exported in STL format, and then into the FreeForm Modeling System for modification and smoothing, followed by image registration of the liver with the ductal system and the calculi.</p><p><b>RESULTS</b>The reconstructed liver model accurately represented the actual size of the liver and its anatomic landmarks, and by adjusting the transparency of the liver, the hepatic and intrahepatic arteries, veins, the portal vein, some abdominal vessels and the biliary system with the calculi were clearly visualized. The calculi in the intrahepatic and extrahepatic bile ducts were distinct in terms of the location and number, and dilation and stenosis of the intrahepatic and extrahepatic bile ducts were also clearly observed. The model presented with realistic profile of the liver that allowed vivid 3D observation. The model also allowed zooming and rotation for observation in full views.</p><p><b>CONCLUSIONS</b>The reconstructed model of the liver and its ductal system can be useful for preoperative planning and intraoperative complete removal of the calculi from the bile duct, and for the bile duct dilation and stenosis detected in the model, appropriate measures should be taken to reduce the residual calculi and prevent reoccurrence.</p>

Study on the three dimensional hepatic virtual operation based on the data of 64-slice helical CT scanning / 中华外科杂志

<p><b>OBJECTIVE</b>To study the surgery plan and simulation effect of the three dimensional (3D) hepatic virtual operation based on the data of 64-slice helical CT scanning and to probe the feasibility of the virtual operation based on the FreeForm Modeling System.</p><p><b>METHODS</b>The volunteer liver was scanned to collect two dimensional (2D) DICOM data of 64-slice helical CT scanning and the 3D hepatic and intrahepatic vessels model were reconstructed by MIMICS software. The reconstructed liver, the intrahepatic vessels model and the artificial tumor models were output into the FreeForm Modeling System in the STL format. The device PHANTOM with the characterization of dynamo-feedback was applied to make the operation on the 3D hepatic.</p><p><b>RESULTS</b>The spatial relationship between the tumour and the intrahepatic vessels were clearly observed by rotation and enlargement of the target. According to the operation principle, the left lobe of liver resection was simulated by manipulating the device PHANToM. Through the liver transparence surface, the intrahepatic vessels were easily distinguished. The operation procedure was accord with the clinic hepatic surgery. Meanwhile, during the operation, by adjusting the incision objective intensity, the dynamo-feedback intensity was definitely touched.</p><p><b>CONCLUSIONS</b>By using the FreeForm Modeling System,the hepatic operation procedure can be simulated ahead of time. The operation complication in the practical surgery can be anticipated and the individualization operation schema can be reasonable instituted.</p>

The research of virtual hepatectomy / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the methodology of mimic resection system on liver.</p><p><b>METHODS</b>Hepatic arteries, portal vein, inferior cava vein, hepatic veins and biliary ducts of liver with integrate hepatic portal were perfused with filling materials in different colors. And then the sample was embedded, frozen and slice-cut to obtain serial sectional images. After image registration and segmentation, the 3D reconstruction model which contained the liver's surface and its internal structures was constructed with MIMICS 9.0. Based on the freeform modeling system and its accessories (the software GHOST and the force-feedback equipment PHANTOM), the virtual hepatectomy system was established which could manipulate the virtual scalpel to perform optional resection on virtual liver model.</p><p><b>RESULTS</b>After slice-cutting the cast liver, 910 serial cross-section images were obtained sharply and clearly. The 3D reconstructed liver model looked like the liver sample exactly, and could be magnified, contracted and rotated. In the virtual surgery system with good interaction, powerful immersion and great imagination, the virtual scalpel could be manipulated to perform optional resection on 3D liver model with the haptic device (PHANTOM).</p><p><b>CONCLUSIONS</b>The 3D visualized liver and the virtual hepatectomy system has been satisfactorily developed using the hepatic serial sectional images. The process of simulation operation was consistent with clinical practice.</p>