OsiriX

OsiriX is an image processing software package for handling DICOM images (files with the extension ".ima", ".dcm" or".DCM"). These files are produced by medical imaging equipment (MRI, CT, PET, etc). OsiriX can also read many other file formats: TIFF (8,16, 32 bits), JPEG, PDF, AVI, MPEG and Quicktime. OsiriX is open source software and can be downloaded free of charge from http://homepage.mac.com/rossetantoine/osirix/Index2.html Currently OsiriX is only available for the Mac (running on Os/X) but there has been talk of a port for linux (no action on this yet other than a newsgroup starting up which seems to be inactive at the moment).

OsiriX has been specifically designed for navigation and visualization in multiple dimensions (including time). The 3D Viewer offers all modern rendering modes: Multiplanar reconstruction (MPR), Surface Rendering, Volume Rendering and Maximum Intensity Projection (MIP).

The OsiriX website includes a large number of screenshots showing what can be accomplished with OsiriX. http://homepage.mac.com/rossetantoine/osirix/Index2.html

A good introduction to some of the 3D rendering modes and how they work can be found here: http://en.wikibooks.org/wiki/Basic_Physics_of_Nuclear_Medicine/Three-Dimensional_Visualization_Techniques I recommend reading through this to gain an understanding of the rendering modes available to you in OsiriX.

The online manual for OsiriX can be found here: http://en.wikibooks.org/wiki/Online_OsiriX_Documentation It is not particularly detailed and I did not find it very helpful. It is also outdated and some of the info is no longer relevant. For example it shows a 3D orthogonal MPR view but this feature is no longer in OsiriX.

There is also an online tutorial avaiable here: http://seminars.apple.com/seminarsonline/osirixintro/apple/index1.html Viewing the tutorial requires registration but this is free. The tutorial is excellent and coupled with exploring OsiriX is a great way to get a handle on the features.

There is a dedicated newsgroup for OsiriX users which requires registration: http://tech.groups.yahoo.com/group/osirix/ This is a very active group and a quick way to get answers to any questions.

OsiriX runs ok on the institute imac (with 1GB of ram), although performance is only acceptable with relatively small image sets. Working with larger image sets would require more memory. Apple recommends a minimum of 2GB and preferably 3GB. If we want to do any work with lung images such as MPI, segmentation, etc, this can not be done until the imac gets a memory upgrade.

Digitisation does not appear to be supported. Some of the viewer modes include the ability to add points but there does not appear to be any way of exporting the coordinates of these points.