Value of a virtual hepatic segment model in assisting in the ultrasonic localization of intrahepatic lesions / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>During scanning of the right hypochondrium and right intercostal regions with an ultrasonic transducer, several ultrasonic images of oblique sections are obtained. It is still a challenge for ultrasonography to divide these non-conventional sections into an accurate hepatic segmentation pattern. The aim of this research was to investigate the value of the virtual hepatic segment model (VHSM) in assisting the ultrasonic localization of space-occupying hepatic lesions.</p><p><b>METHODS</b>VHSM was constructed via 3D reconstruction according to the first Chinese visible human dataset. Preoperative ultrasonography, contrast-enhanced CT scan and VHSM techniques were performed in 100 patients with space-occupying focal lesions in the liver parenchyma for segmental localization. The results of these three techniques were compared with the operative findings.</p><p><b>RESULTS</b>VHSM was successfully detected on 2D sectional images by 3D reconstruction through surface rendering and volume rendering. The model could simulate ultrasonic directions to conduct a virtual dissection on any section plane, and fine liver segmentation could be displayed in any virtual plane. In 100 patients, there were 112 liver space-occupying focal lesions distributed in 148 liver segmentations. Regarding the positioning accuracies for lesions of different sizes and the lesion segmental distribution accuracies estimated using the three methods mentioned above, ultrasonography exhibited a significantly lower accuracy than VHSM for the segmental localization of lesions (P < 0.05), and contrast-enhanced CT was not significantly different from ultrasonography plus VHSM (P > 0.05).</p><p><b>CONCLUSION</b>VHSM increased the accuracy of ultrasonic localization of space-occupying hepatic lesions, particularly in hepatic hypovascular regions.</p>

3-Dimensional model reconstruction of penis and surrounding tissue / 中华整形外科杂志

<p><b>OBJECTIVE</b>To evaluate the feasibility of 3-Dimensional (3-D) model reconstruction of penis and surrounding structures based on magnetic resonance images, which may provide the model building method for modeling surgery of individual penoplasty.</p><p><b>METHODS</b>Magnetic resonance (MR) images of penis with different imaging parameters were evaluated. With the surface rendering construction, the 3D virtual model was established by Amira software.</p><p><b>RESULTS</b>The anatomical details imaging is better in T2-weighted fast spin-echo images with 3.0 mm slice thickness. The established model based on the MR images can show the soft-tissue, suspensory ligament of the penis. The suspensory ligament stretches between the pubic symphysis and the corpora cavernosa. The penile roots attach to inferior ramus of pubis.</p><p><b>CONCLUSIONS</b>MR imaging provides enough anatomical information for modeling. It can be used for the development of model surgery system of individual penoplasty.</p>

Three-dimensional reconstruction of digitized human liver: based on Chinese Visible Human / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Comparing with two dimensional (2D) imaging, both in diagnosis and treatment, three dimensional (3D) imaging has many advantages in clinical medicine. 3D reconstruction makes the target easier to identify and reveals the volume and shape of the organ much better than 2D imaging. A 3D digitized visible model of the liver was built to provide anatomical structure for planing of hepatic operation and for realizing accurate simulation of the liver on the computer.</p><p><b>METHODS</b>Transverse sections of abdomen were chosen from the Chinese Visible Human dataset. And Amira software was selected to segment and reconstruct the structures of the liver. The liver was reconstructed in three-dimensions with both surface and volume rendering reconstruction.</p><p><b>RESULTS</b>Accurately segmented images of the main structures of the liver were completed. The reconstructed structures can be displayed singly, in small groups or as a whole and can be continuously rotated in 3D space at different velocities.</p><p><b>CONCLUSIONS</b>The reconstructed liver is realistic, which demonstrates the natural shape and exact position of liver structures. It provides an accurate model for the automated segmentation algorithmic study and a digitized anatomical mode of viewing the liver.</p>

Development and clinical application of 3D operative planning system of live in virtual reality environments / 中华外科杂志

<p><b>OBJECTIVE</b>To explore and develop three-dimension (3D) virtual reality (VR) liver model and convert computed tomography data into a fully 3D VR environment for display, measure and manipulation.</p><p><b>METHODS</b>3D-reconstruction of liver was restored from spiral computed tomography (CT) data by using LiVirtue software. Dextrobeam was used to view the 3D model in the VR environment. The liver and its anatomic structure were reconstructed to illuminate the location of the tumor and its related vessels.</p><p><b>RESULTS</b>3D models of liver, tumor and their relative vessels were reconstructed successfully. These models could be viewed and manipulated in the VR environment on personal computer.38 patients underwent liver resection, including 21 right hemihepatectomy, 14 left hemihepatectomy and 3 extended right hemihepatectomy. The intraoperative contrast with preoperative simulation confirmed the reliability of our 3D operative planning system.</p><p><b>CONCLUSIONS</b>The preoperative simulation in 3D VR facilitated liver resection by the ability to view tumor and its relative vessels. This preoperative estimation from 3D model of liver benefits a lot to complicated liver resection.</p>

Visualization of the adult penis and adjacent structure of the Chinese visible human / 中华整形外科杂志

<p><b>OBJECTIVE</b>To build digitized visible model of the adult penis and adjacent structure of the Chinese visible human, providing morphological data for plastic plerosis of external genitals diagnosis and the adult penis surgery planning.</p><p><b>METHODS</b>Cross-sectional images of fresh tissues from the Chinese visible human dataset and the visible penis and adjacent structure dataset were reviewed, the structures of the penis and adjacent structure were confirmed on a section-by-section basis. Three-dimensional computer reconstructions of the penis and adjacent structure were generated from these data by surface rendering.</p><p><b>RESULTS</b>The quality of the computerized 3D-reconstructed images was distinct and perfect. The adult penis and adjacent structure were all reconstructed and displayed jointly. All reconstructed structures can be represented individually or jointly. Any diameter and angle of the structures reconstructed could be measured conveniently.</p><p><b>CONCLUSIONS</b>The digitized model of the penis and adjacent structure offer unique insights into the complex penis anatomy, providing morphological data for plastic plerosis of external genitals diagnosis and surgery planning.</p>