Neuroradiology (2004) 46: S193
Can you think of neuroradiology without computed tomography (CT) and
magnetic resonance imaging (MRI)? Clearly not; both imaging modalities
have become routine in the last few decades. However, “routine” does not
mean that these methods are no longer evolving.
During the satellite symposium held on the occasion of the annual
ESNR meeting (Aachen, September 8–11, 2004) we were presented with
the most recent scientific data on perfusion CT and MRI, time-resolved MR
angiography and the latest techniques. This supplement gathers together
the papers given at the symposium.
The articles by Drs. K.A. Miles and M. Essig review the advantages and
limitations of perfusion CT and MRI, respectively, and draw comparisons
between the two modalities. Brain perfusion imaging with CT is an easy-to-
perform technique, particularly applicable in patients presenting with
stroke, head injury, subarachnoid hemorrhage or who require radiotherapy
planning. Combined PET-CT systems offer additional opportunities to im-
prove the evaluation of patients with cerebral ischaemia or tumors, through
providing information on the relationship between cerebral blood flow and
metabolism. Conversely, MR perfusion offers the advantage of better spa-
tial resolution for improved depiction of anatomy. Contrast-enhanced and
non-enhanced techniques to measure cerebral perfusion with MRI and CT
are presented, highlighting the advantages of contrast enhancement for the
acquisition of physiological information on pathological processes in the
central nervous system.
Meanwhile, articles by Drs. B. Schuknecht and T. Krings debate the
advantages and limitations of CT and MR angiography, respectively.
Dr. Schuknecht’s article presents the advantages of CT angiography vs.
both digital subtraction angiography (DSA) and MR angiography, as well
as the essential role played by contrast media with high iodine concentra-
tions in the acquisition of detailed, high resolution CT angiograms.
A major advantage of conventional DSA is its high temporal resolution,
which is crucial in some clinical situations such as in the evaluation of rapid-
flow vascular malformations. Dr. T. Krings’ paper highlights the advances
recently made in time-resolved MR angiography, with particular reference
to the improvements in gradient hardware performance and imaging tech-
niques that now permit image acquisition with a temporal resolution similar
to that achievable with conventional DSA.
The future of diagnostic imaging clearly lies beyond mere morphology. We
will be able to look at brain function in greater detail and to replace invasive
methods, whenever possible. It is not a secret that improved contrast agents
are helpful and in many cases necessary in getting beyond morphology.
There are longstanding collaborations between contrast agent manufac-
turers and neuroradiologists, and this is an excellent example of how indus-
trial and scientific research can be combined for the patient’s advantage.
Prof. Dr. med. M. Forsting
Chairman of Radiology and Neuroradiology,
University of Essen, Germany
Imaging 2004: morphology and more