The image also has a centimeter scale on it from which we can ascertain the pixel sizes. We will assume that the horizontal and vertical pixel dimensions are the same. For three-dimensional reconstructions, we will assume that the horizontal dimension of the image represents the X.

axis in Osirix, the vertical dimension on the image represents the Y. axis in Osirix, and the different images are taken perpendicular to the Z. Using the length measurement tool in Osirix, we can determine the number of pixels it takes to traverse 15 cm or 150 mm along the ruler which is included in the image.įrom the image above, measuring 150 mm along the ruler, we see that the length is 456.725 pixels. For our training purpose, 0.33 mm should be fine for the pixel size with an image spacing of 6mm from the given spacing of the images. We now attempt to perform a 3-D volume rendering as shown in the image above. Unfortunately, we encounter a volume rendering error as demonstrated in the image below. There is not much information provided by the error message as how to proceed further. So we go back and look at the original files that were imported into Osirix using the Inspector. This demonstrates that the images are nearly the same dimensions in horizontal and vertical pixels, however, they are slightly different sizes. Because of this, the stack of images cannot be aligned pixel by pixel from one image to the next. The different image sizes are seen in the following screen capture. Using a graphical editing program, such as Seashore for the Mac, which is free, the images were resized so that all of them would be 605 x 455 pixels.

Osirix lite draw roi