Reproducibility of dynamic and diffusion weighted 3 Tesla MRI

In former research, we studied the characteristics of tumour vascularisation.
We showed that the reproducibility of parameters measured by DCE-MRI can be
improved by normalising the data with concentration-time graphs of the contrast
medium Gadolinium in the supplying vains of the tumour (artery input function,
AIF). In this method we determine the AIF for each DCE-MRI. This leads to a
significant better reproducibility in brain tumours, prostate tumours and head
and neck tumours. (3). A comparable analysis method has been applied to
patientes with liver metastases. This resulted in good reproducibility data as
well (4).

Above described research were perform,ed on a 1.5T MR scanner. Not much is
known about the reproducibility techniques performed on a 3 T MR scanner. In
general the signal/noise ratio increases with higher magnetic fields, which
could lead to a better reproducibility of the data. However, the use of higher
magnetic fields is also associated with a bigger chance of artifacts. The
proposed research is designed to test the reprocucibility of the method of
DCE-MRI contrast and DWI on our current clinical 3 T MR scanner.

In *Pilot study on the influence of Sunitinib on tumour vascularization and
necrosis in patients with renal cell carcinoma* a dynamic contrast enhanced MRI
(DCE-MRI) and diffusion weighted magnetic resonance imaging (DWI) takes place
in the week prior to start with Sunitinib, and after tart op dag 3 en op dag
10. Deze MRI*s worden gemaakt om het effect van Sunitinib op vascularisatie van
de tumor, het bloedvolume van de tumor en necrose in de tumor te bepalen.
Hiertoe worden na de gebruikelijke conventionele anatomische beeldvorming
diffusie gewogen beelden en T2* beelden opgenomen. Het MR contrast middel
Gadolinium (Gd-DTPA) wordt intraveneus toegediend ten behoeve van het
karakteriseren van tumor vasculatuur. Na een tweede intraveneuze bolusinjectie
van Gd-DTPA worden snelle T2* beelden opgenomen om het bloedvolume te bepalen.
De onderzoeken vinden plaats op de klinische 3 T MR scanner. Voor een goede
beoordeling van de data van deze lopende, reeds door het CMO goedgekeurde
studie, zijn gegevens over de reproduceerbaarheid van belang.

To determine the reproducibility for quantitative analysis of MRI with contrast
en diffusion weighted MRI (DWI) if abdominal malignant tumors.

- 20 patients with an abdominal tumour of at least 2 cm diameters will be asked
to participate
- Within one week a DCE-MRI and DWI (as described in the original protocol)
will be performed twice
- The MRIs will be performed at least 24 hours after each other and maximum
within a week, at the clinical 3T MR scanner
- Before the first DCE-MRI, a bloodsample will be taken to examine the liver
enzyms (AST, ALT, alkalic phosphatase, gGT, LDH). Furthermore, a serum sample
will be taken to examinen angiogentic facors.
- Each MRI takes about 45 minutes

The patient will undergo twice a MRI. There is a limited risk of allerguy to
contrast, a haematoma. Furthermore, a very limted risk of contrast nephropathy
exists.