MnDPDP-enhanced magnetization transfer MR imaging: implications for effective liver imaging.
The benefit of combining magnetization transfer (MT) MR imaging technique with liver-specific contrast agent manganese dipyridoxyldiphosphate (MnDPDP) was assessed in our experimental investigation. The study was accomplished by imaging a phantom containing serial concentrations of MnDPDP in cross-linked bovine serum albumin (BSA) with various protein concentrations. A 0.1T clinical MR imager with different parameters for MT and conventional MR sequences were used. The combination of an offset frequency of 8 kHz and an amplitude of 25 microT produced nearly maximal MT effect for all protein samples either without MnDPDP or with different MnDPDP concentrations. With long TRs (TR > 200 ms) MT dramatically improved CNR in conjunction with MnDPDP. With short TRs, the gain in CNR with MT was negligible. However, long TRs with increased number of images are beneficial in liver imaging. We conclude that MT like preparation pulse is useful when paramagnetic contrast agents such as MnDPDP are employed.
Halavaara
Juha
J
Department of Radiology, Helsinki University Central Hospital, Haartmaninkatu 4, 00290, Helsinki, Finland. juha.halavaara@hus.fi
Abo-Ramadan
Usama
U
Markkola
Antti
A
Aronen
Hannu
H
Häkkinen
Anna-Maija
AM
D003287:Contrast Media; D004492:Edetic Acid / Q000031:analogs & derivatives; D006801:Humans; D007089:Image Enhancement; D008099:Liver / Q000473:pathology*; D008107:Liver Diseases / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D019047:Phantoms, Imaging; D011732:Pyridoxal Phosphate / Q000031:analogs & derivatives
D003287:Contrast Media; D011732:Pyridoxal Phosphate; D004492:Edetic Acid; C060076:N,N'-bis(pyridoxal-5-phosphate)ethylenediamine-N,N'-diacetic acid