Click on image to view larger version.



FIG 1. Opacity charts of the signal intensity distribution for the 3D MR cisternograms.

A, Opacity chart for the conventional 3D MR cisternogram, showing a square curve with a threshold range of 100–500 (100% opacity level), and color-rendered in green (threshold range 100–490) and red (490–500).

B, Opacity chart for the transparent 3D MR cisternogram, showing square curves, one with a threshold range of 480–500 (100% opacity level), color-rendered in green (threshold range 480–490) and red (490–500), and the other with a threshold range of 100–250 (100% opacity level), color-rendered in blue.