Optimized visualization of contrast medium dependent differences in CT/MRI scans by RGB transformation.

OBJECTIVE: In order to be able to assess the contrast medium enhancement of vessels and regions with disturbed blood-brain barrier, the neurosurgeon must mentally perform a subtraction of the corresponding native and contrast-enhanced scans of the CT or MRI. The principle disadvantages of this comparison are the amount of time required and the potential errors which may result from false interpretation. METHODS: The process presented here combines corresponding scans without and with contrast medium offline on a PC. In this process each couple of the black and white scans is assigned to the colour channels of the RGB system (red, green, blue) and transformed to one colour picture of the RGB colour space (additive colour mixture). RESULTS: We demonstrate that contrast medium-dependent changes can be represented in a colour contrast of complementary colours in one single picture. Additionally, the unchanged structures remain in the black and white contrast as they were before. CONCLUSION: Thanks to the optimized visualization of contrast medium dependent differences there are besides saving in time further advantages such as the reduced amount of pictures and an objective representation.