Quantification of liver blood volume: comparison of ultra short TI inversion recovery echo planar imaging (ULSTIR-EPI), with dynamic 3D-gradient recalled echo imaging.
An ultra-short TI inversion recovery echo-planar imaging (ULSTIR-EPI) sequence was designed to reduce the influence of water exchange on fractional tissue blood volume (BV) estimation by measurement of T1-changes induced by a gadolinium-based macromolecular contrast medium (MMCM). Fractional liver BV in rats, estimated by ULSTIR-EPI was compared for accuracy to a fast T1-weighted three-dimensional gradient-echo (3D-SPGR, 3D-spoiled gradient recalled acquisition in a steady state) sequence using an in vitro inductively coupled plasma atomic emission spectroscopy (ICP-AES) assay for BV as a standard. Liver images for fractional BV estimation were acquired in eight rats using both ULSTIR-EPI and 3D-SPGR before and after (within 3 to 12 min) intravenous bolus administration of albumin-Gd-DTPA30 (0.05 mmol Gd/kg). Whereas both MR techniques may be useful for fractional tissue BV estimation, ULSTIR-EPI offers certain advantages including greater accuracy, direct T1 maps, and minimization of transendothelial proton exchange effects. 3D-SPGR imaging offers better spatial resolution, current availability on standard clinical MR systems, and acceptable accuracy.
Schwickert
H C
HC
Department of Radiology, University of California, San Francisco 94143, USA.
Roberts
T P
TP
Shames
D M
DM
van Dijke
C F
CF
Disston
A
A
Mühler
A
A
Mann
J S
JS
Brasch
R C
RC
D000418:Albumins; D000818:Animals; D001810:Blood Volume; D001811:Blood Volume Determination; D003287:Contrast Media; D017352:Echo-Planar Imaging / Q000379:methods*; D005260:Female; D019786:Gadolinium DTPA; D007091:Image Processing, Computer-Assisted; D008099:Liver / Q000033:anatomy & histology / Q000098:blood supply*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009942:Organometallic Compounds; D004369:Pentetic Acid / Q000031:analogs & derivatives; D051381:Rats; D011916:Rats, Inbred F344
D000418:Albumins; D003287:Contrast Media; D009942:Organometallic Compounds; C058946:albumin-(gadolinium-DTPA); D004369:Pentetic Acid; D019786:Gadolinium DTPA