Surface models of the human body are used in electrocardiography to:
Anatomical data were obtained from the Visible Human Project. In work done previously by Dr. Arthur, points on the surface of the body were extracted from slices of the body from the Visible Human Project. After resampling the data points, they were plotted as contours at particular value along the axis of the body. Contours were separated by 10 mm. The image below displays contours from the head and shoulders in millimeters.
The three main steps in generating a surface from anatomical data using IsoSurf are:
|This plot displays the contours in millimeters taken from one image of the Visible Human Male. The contours were formed by joining surface points in sequence.|
|This image displays the contour above filled using a polygon-fill algorithm.|
|Using multiple such filled slices, the surface was generated then displayed using Matlab.|
In the java applet below, you can view a 3D surface model of the torso. The caps at the top and bottom of the model were omitted so that the interior is also visible.
Press right mouse button to select major interaction mode from popup menu, or use keyboard keys to temporarily switch between different modes (just keep a button pressed to switch mode temporarily). Some essential modes are:
|o||Rotate surface (this Orbit mode is the default mode)|
|s||Scale surface, drag in vertical direction|
|t||Translate surface in viewing plane|
|r||Reset camera and display, object returns to default position|
F1 or Ctrl-s
|Show control window|
|Help||With all keyboard shortcuts, and help on problems.|
To modify appearance of the geometry press F1 or Ctrl-s to open the control panel and select the material panel (if not visible) via menu Inspector - Object - Material. Be sure that the mouse focus is inside the viewer otherwise, e.g., the window manager might react. To hide the control panel press F2.The java applet is made possible by using JavaView, a freely available 3D geometry viewer and a mathematical visualization software which can be obtained from JavaView's website
Sharad P. Bhooplapur
Edited by R. M. Arthur, 9 September 2005.