It is a well known gift of true flow cytometrists to be able to see more in their data than actually exists. It sometimes seems more difficult to visualize what really is there. While we are quite comfortable interpreting one-parameter histograms and also two-parameter displays of various formats, we may experience uneasiness at the thought of three parameters, and any more than that may be regarded with the same awe as is engendered in thinking about the infinity of space. As "virtual reality" techniques have not yet been added to the analytical tool boxes of very many flow cytometry laboratories, it appears useful to install a stopgap immediately which requires only simple software and no expensive hardware.
Hence, a simple solution to the "three+-parameter" display problem is here proposed: Well known 3D plotting techniques are used, but with a "magic box" replacing the colour-coded stereo spectacles. This allows 3D stereo viewing but with the retention of colour as an indicator of cell information not directly displayed. Thus, while the 3D dot plot can display three flow cytometric parameters directly, the colour of each dot can additionally reflect a cell's properties in a fourth parameter or, most usefully, the result of a cluster assignment based on all measured parameters. Animation of the display (continuous rotation or tilting; not shown in this static presentation) has also been found to add to its effectiveness.
The structure of the magic box is quite straightforward and can be reproduced by flow cytometric magicians at other sites.
