The lack of depth perception and spatial orientation in two-dimensional image of traditional laparoscopy require long-term training of the surgeons. Three-dimensional (3D) laparoscopy provides stereoscopic visions as compared to monocular views in a traditional laparoscopic system. In this review, the authors summarize the clinical application of 3D laparoscopy and its current research progress.
Imaging, Three-Dimensional ; instrumentation ; methods ; Laparoscopy ; methods

The positioning error in radiotherapy is one of the most important factors that influence the location precision of the tumor. Based on the CT-on-rails technology, this paper describes the research on measuring the positioning error in radiotherapy by comparing the planning CT images with the treatment CT images using 3-dimension (3D) methods. It can help doctors to measure positioning errors more accurately than 2D methods. It also supports the powerful 3D interaction such as drag-dropping, rotating and picking-up the object, so that doctors can visualize and measure the positioning errors intuitively.
Humans ; Imaging, Three-Dimensional ; Radiotherapy ; methods

This paper addressed the volume measurement of 3D ultrasound imaging system. Two different phantoms used in the measurement of volume of the 3D ultrasound imaging system were built, i.e., water phantom and agar phantom. The experiments demonstrated that as the increase of scan depth, the volume measurement accuracy is varied from 4% to 7% in water and 6% to 10% in agar. The phantoms and the volume measurement of the 3D ultrasound imaging system provides a basis for the establishment of testing standard and clinical application of 3D ultrasound imaging system.
Imaging, Three-Dimensional ; Phantoms, Imaging ; Ultrasonography ; instrumentation ; methods

A Fast Multi-resolution Volume Rendering Method (FMVRM) based on wavelet and Shear-Warp is herein proposed. In this method, the medical volume data is compressed using wavelet transformation first. Then based on the set resolution, the medical volume data is decompressed guided by Opacity transfer function (OTF). Finally, the 3D medical image is reconstructed on the basis of Shear-Warp using Block-based run length encoded (BRLE) data structure, in which, the aliasing artifacts resulting from under-sampling in Shear-Warp is avoided by the pre-integrated volume rendering technology. Experiments demonstrate the good performance of the proposed method.
Algorithms ; Artifacts ; Data Compression ; methods ; Humans ; Imaging, Three-Dimensional ; methods

A detailed review is given in this paper on various current 3D display methods for sequential 2D medical images and the new development in 3D medical image display. True 3D display, surface rendering, volume rendering, 3D texture mapping and distributed collaborative rendering are discussed in depth. For two kinds of medical applications: Real-time navigation system and high-fidelity diagnosis in computer aided surgery, different 3D display methods are presented.
Algorithms ; Image Processing, Computer-Assisted ; methods ; Imaging, Three-Dimensional ; methods

A method of acquiring radial pulse information from the grid-net area on every pulse image frame is proposed based on the principle of lens imaging and the characteristics of image data. The radial pulse image data are collected by the pulse image sensor. Multi-points out-of-plane displacements of the pulse are acquired by the method. And the membrane surfaces are reconstructed, then the 3D information of the pulse can be observable.
Image Interpretation, Computer-Assisted ; methods ; Imaging, Three-Dimensional ; methods

BACKGROUND: Recently, three-dimensional (3D) printing has been hailed as a disruptive technology in dentistry. Among 3D printers, a digital light processing (DLP) 3D printer has certain advantages, such as high precision and relatively low cost. Therefore, the latest trend in resin crown manufacturing is the use of DLP 3D printers. However, studies on the internal fitness of such resin crowns are insufficient. The recently introduced 3D evaluation method makes it possible to visually evaluate the error of the desired area. The purpose of this study is to evaluate the internal fitness of resin crowns fabricated a by DLP 3D printer using the 3D evaluation method.METHODS: The working model was chosen as the maxillary molar implant model. A total of 20 resin crowns were manufactured by dividing these into two groups. One group was manufactured by subtractive manufacturing system (PMMA), while the other group was manufactured by additive manufacturing system, which uses a DLP 3D printer. Resin crowns data were measured using a 3D evaluation program. Internal fitness was calculated by root mean square (RMS). The RMS was calculated using the Geomagic Verify software, and the mean and standard deviation (SD) were measured. For statistical analysis, IBM SPSS Statistics for Windows ver. 22.0 (IBM Corp., USA) was used. Then, independent t-test was performed between the two groups.RESULTS: The mean±SD of the RMS were 41.51±1.51 and 43.09±2.32 for PMMA and DLP, respectively. There was no statistically significant difference between PMMA and DLP.CONCLUSION: Evaluation of internal fitness of the resin crown made using a DLP 3D printer and subtractive manufacturing system showed no statistically significant differences, and clinically acceptable results were obtained.
Crowns ; Dentistry ; Imaging, Three-Dimensional ; Methods ; Molar ; Polymethyl Methacrylate ; Printing, Three-Dimensional

OBJECTIVETo establish the three-dimensional (3D) visible models of the anatomical structures of the anterior approach to the upper thoracic spine (UTS) for anatomic study and preoperative planning of the UTS.

METHODSSectional images from the superior margin of the first thoracic vertebral body to the inferior margin of the fifth thoracic vertebral body were acquired through the Chinese Visible Human Female (VCHF) database which was collected by the Third Military Medical University. These images were imported into Photoshop CS, cut automatically and converted into a JPEG format. Surface and volume reconstruction were performed by 3D Doctor 3.5 and Amira 4.0 software programs on an ordinary personal computer respectively.

RESULTSThe surface reconstruction model could be rotated at any angle and observed from any direction. And the reconstructed structures of the anterior approach to the UTS could be displayed individually or as a composite with any other selected structure. The volume reconstruction displayed abundant internal details of the reconstructed images in transverse, coronal, sagittal, and random oblique sections.

CONCLUSIONThree-dimensional visible models of the anatomical structures of the anterior approach to the UTS based on the sectional images of VCHF can clearly display the morphology, spatial orientation and adjacent relationship of every structure. These models are very helpful to the anatomy study and preoperative planning of this complex anatomic region.

In this paper, the principle of computer vision was introduced and several typical radiotherapy devices based on computer vision were described, including their principle and applications.
Audiovisual Aids ; Imaging, Three-Dimensional ; Radiotherapy, Computer-Assisted ; methods ; Software

The aim of this paper is to study the methods of 3D visualization and the 3D interactive clipping of CT/MRI image sequence in arbitrary orientation based on the Visualization Toolkit (VTK). A new method for 3D CT/MRI reconstructed image clipping is presented, which can clip 3D object and 3D space of medical image sequence to observe the inner structure using 3D widget for manipulating an infinite plane. Experiment results show that the proposed method can implement 3D interactive clipping of medical image effectively and get satisfied results with good quality in short time.
Algorithms ; Image Interpretation, Computer-Assisted ; methods ; Imaging, Three-Dimensional