Computer Simulation for the Stereotactic Placement of Interstitial Radionuclide Sources into Computed Tomography-defined Tumor Volumes

Neurosurgery ◽  
1984 ◽  
Vol 14 (4) ◽  
pp. 442-448
Author(s):  
J. Kelly Patrick ◽  
A. Kall Bruce ◽  
Goerss Stephan
Keyword(s):  
Computed Tomography ◽  
Computer Simulation ◽  
Solid Tumor ◽  
Tumor Volume ◽  
Three Dimensional ◽  
Radioactive Source ◽  
Stereotactic Frame ◽  
Ct Data ◽  
Ct Slices

Abstract This report describes a method for the preoperative determination of radioactive interstitial source placement within computed tomography (CT)-defined tumor boundaries. The method utilizes CT data obtained under stereotactic conditions. Tumor boundaries are digitized from CT slices and are retained in a three-dimensional computer matrix. A solid tumor volume is created by an interpolation program and may be sliced orthogonal to any specific stereotactic surgical view line. The surgeon may simulate radioactive source placement within the slices and view the resultant isodose configuration against tumor contours on successive slices. Once the best source placement has been determined, the computer outputs the mechanical adjustments that will be necessary on a stereotactic frame located in the operating room for the stereotactic placement of each source and gives the length of each source. Sources are stereotactically implanted utilizing a double-catheter afterloading technique.

Intellectual Measuring Complex for Control of Geometrical Parameters of Aviation Details

2020 ◽  
pp. 352-371
Author(s):  
Mariia Kataieva ◽  
Alina Yurchuk
Keyword(s):  
Computer Simulation ◽  
Measurement Error ◽  
Three Dimensional ◽  
Geometric Parameters ◽  
Measurement Process ◽  
Geometrical Parameters ◽  
Automated Method ◽  
Measuring Complex ◽  
Graphic Depiction

This chapter proposes a new automated method of measuring complex three-dimensional surfaces of aircraft parts in static and dynamic modes. The method allows conducting measurements in closed conditions and at the site of the aircraft disposition. The method consists in the continuous determination of the coordinates of the points of the surface of the detail and their representation in a three-dimensional graphic depiction. New methods of measuring the geometric parameters of parts with the complex spatial surface are suggested. This opens the prospect for the development of new ways of measuring geometric parameters of parts in real-time with high metrological characteristics and computer simulation of the measurement process. The differential-digital method is based on the suggested zero-coordinate principle of the measurement process which involves simultaneous parts availability check, and connects measurement result obtained which provided a reduction in the order of measurement error.

Adaptive Fuzzy Segmentation of Tumors in Three-Dimensional Computed Tomography (CT) Image Data

2007 ◽  
Author(s):  
Jung Leng Foo ◽  
Go Miyano ◽  
Thom Lobe ◽  
Eliot Winer
Keyword(s):  
Computed Tomography ◽  
Fuzzy Inference ◽  
Three Dimensional ◽  
Fuzzy Rule ◽  
Region Of Interest ◽  
Image Data ◽  
Ct Image ◽  
Inference System ◽  
Ct Data ◽  
Fuzzy Segmentation

The continuing advancement of computed tomography (CT) technology has improved the analysis and visualization of tumor data. As imaging technology continues to accommodate the need for high quality medical image data, this encourages the research for more efficient ways of extracting crucial information from these vast amounts of data. A new segmentation method using a fuzzy rule based system to segment tumors in a three-dimensional CT data has been developed. To initialize the segmentation process, the user selects the region of interest (ROI) within the tumor in the first image of the CT study set. Using the ROI’s spatial and intensity properties, fuzzy inputs are generated for use in the fuzzy inference system. From a set of predefined fuzzy rules, the system generates a defuzzified output for every pixel in terms of similarity to the object. Pixels with the highest similarity values are selected to be the tumor. This process is repeated for every subsequent slice in the CT set, and the segmented region from the previous slice is used as the ROI for the current slice. This creates a propagation of information from the previous slices, to be used to segment the current slice. The membership functions used during the fuzzification and defuzzification processes are adaptive to the changes in the size and pixel intensities of the current ROI. The proposed method is highly customizable to suit different needs of a user, requiring information from only a single two-dimensional image. Implementing the fuzzy segmentation on two distinct CT sets, the fuzzy segmentation algorithm was able to successfully extract the tumor from the CT image data. Based on the results statistics, the developed segmentation technique is approximately 96% accurate when compared to the results of manual segmentations performed.

scholarly journals 3D immersive visualization of micro-computed tomography and XRD texture datasets

2019 ◽  
Vol 34 (2) ◽  
pp. 97-102
Author(s):  
M. A. Rodriguez ◽  
T. T. Amon ◽  
J. J. M. Griego ◽  
H. Brown-Shaklee ◽  
N. Green
Keyword(s):  
Computed Tomography ◽  
Texture Analysis ◽  
Mechanical Strain ◽  
Three Dimensional ◽  
Multidimensional Analysis ◽  
Micro Computed Tomography ◽  
X Ray ◽  
3D Data ◽  
Pole Figures ◽  
Ct Data

Advancements in computer technology have enabled three-dimensional (3D) reconstruction, data-stitching, and manipulation of 3D data obtained on X-ray imaging systems such as micro-computed tomography (μ-CT). Likewise, intuitive evaluation of these 3D datasets can be enhanced by recent advances in virtual reality (VR) hardware and software. Additionally, the generation, viewing, and manipulation of 3D X-ray diffraction datasets, such as pole figures employed for texture analysis, can also benefit from these advanced visualization techniques. We present newly-developed protocols for porting 3D data (as TIFF-stacks) into a Unity gaming software platform so that data may be toured, manipulated, and evaluated within a more-intuitive VR environment through the use of game-like controls and 3D headsets. We demonstrate this capability by rendering μ-CT data of a polymer dogbone test bar at various stages of in situ mechanical strain. An additional experiment is presented showing 3D XRD data collected on an aluminum test block with vias. These 3D XRD data for texture analysis (χ, ϕ, 2θ dimensions) enables the viewer to visually inspect 3D pole figures and detect the presence or absence of in-plane residual macrostrain. These two examples serve to illustrate the benefits of this new methodology for multidimensional analysis.

Computed Tomography-directed Stereotaxy for Biopsy and Interstitial Irradiation of Brain Tumors: Technical Note

Neurosurgery ◽  
1982 ◽  
Vol 11 (1_pt_1) ◽  
pp. 38-42 ◽  
Author(s):  
Alexander R. MacKay ◽  
Philip H. Gutin ◽  
Yoshio Hosobuchi ◽  
David Norman
Keyword(s):  
Computed Tomography ◽  
Brain Tumors ◽  
Radioactive Source ◽  
Technical Note ◽  
Accurate Diagnosis ◽  
Diagnosis And Treatment ◽  
Interstitial Irradiation ◽  
Computed Tomographic ◽  
Stereotactic Frame ◽  
Stereotactic System

Abstract A computed tomographic-stereotactic system based on the Leksell stereotactic frame has been used to implant radioactive 125I sources into (28 procedures) or to biopsy (2 procedures as biopsy only, 2 in conjunction with the implantation of a radioactive source) malignant brain tumors. In every instance, the selected target was reached precisely, allowing accurate diagnosis and treatment.

Experimental Determination of Computed Tomography Settings for Jaw Scanning

1970 ◽  
Vol 111 (5) ◽  
pp. 129-132
Author(s):  
R. Adaskevicius ◽  
D. Macianskytė ◽  
E. Monastyreckiene
Keyword(s):  
Computed Tomography ◽  
Laser Scanner ◽  
Spiral Ct ◽  
Computer Models ◽  
Ct Scanner ◽  
Experimental Identification ◽  
Ct Data ◽  
3D Computer Model ◽  
Design And Manufacture

Aim of our study is to develop a method for the experimental identification of the settings of a computed tomography (CT) scanner used for scanning of human jaw. I this case, CT can be used for rapid prototyping of human jaw, design and manufacture of implants. The experimental identification of settings of a computed tomography scanner is done by comparing 3D computer models built using different data acquisition technologies: CT scanner and 3D laser scanner. The modified Iterative Closest Points algorithm is used for alignment of 3D computer models, obtained using different scanning methods. The different test objects were scanned using a spiral CT scanner and 3D laser scanner for testing the method. 3D computer models were compared uding the mean square value of distance between two surfaces. The test results indicate hardware and software parameters impacting on the accuracy and surface quality of 3D computer model reconstructed from CT data. Ill. 5, bibl. 7 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.373

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