[T1-weighted dynamic MRI with new superparamagnetic iron oxide particles (Resovist): results of a phantom study as well as 25 patients].
OBJECTIVE
Evaluation of the diagnostic usefulness of the T1-effect of Resovist (SPIO) for dynamic MRI of the liver.


METHODS
In-vitro measurements of a dilution series with T1-weighted FLASH and SE sequences and investigation of 25 patients with known focal liver lesions with a T2-weighted TSE sequence and a dynamic T1-FLASH sequence.


RESULTS
T1-weighted MRI with Resovist in vitro showed a positive enhancement at low concentrations and a negative enhancement at higher concentrations. In-vivo T1-weighted dynamic MRI liver parenchyma demonstrated a positive enhancement 30 s post contrast, followed by a continuous slope of signal intensity and a negative enhancement (> or = 60 s). Spleen, portal venous vessels and haemangiomas showed an early increase in signal intensity followed by a decreasing positive enhancement, but without negative enhancement. During the perfusion phase metastases showed a small but not significant increase in signal intensity. In 80% a positive ring enhancement could be observed around metastases.


CONCLUSIONS
Resovist exhibits a diagnostically useful T1-effect. An evaluation of the perfusion of focal liver lesions during the distribution phase is possible with dynamic T1-weighted MRI. This approach may further improve characterisation of focal liver lesions.
Müller
M
M
Institut für Klinische Radiologie, Westfälische Wilhelms-Universität Münster.
Reimer
P
P
Wiedermann
D
D
Allkemper
T
T
Marx
C
C
Tombach
B
B
Rummeny
E J
EJ
Shamsi
K
K
Balzer
T
T
Peters
P E
PE
D000328:Adult; D000368:Aged; D003287:Contrast Media; D003911:Dextrans; D005260:Female; D052203:Ferrosoferric Oxide; D006391:Hemangioma / Q000175:diagnosis / Q000473:pathology; D006801:Humans; D007501:Iron; D008099:Liver / Q000473:pathology*; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000556:secondary*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D008297:Male; D008875:Middle Aged; D010087:Oxides; D010190:Pancreatic Neoplasms / Q000175:diagnosis / Q000473:pathology; D019047:Phantoms, Imaging; D011168:Portal System / Q000473:pathology; D015203:Reproducibility of Results; D013154:Spleen / Q000473:pathology
D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; D007501:Iron; C065507:ferumoxides; D052203:Ferrosoferric Oxide