Vol. 273, Issue 4, G965-G967, October 1997
SPECIAL COMMUNICATION
Demonstration of changes in fetal liver erythropoiesis using
echo-planar magnetic resonance imaging
K. R.
Duncan1,
P. N.
Baker1,
P. A.
Gowland2,
B.
Issa2,
R.
Moore2,
B.
Worthington3, and
I. R.
Johnson1
1 Department of Obstetrics and
Gynaecology, 3 Department of
Academic Radiology, and
2 Magnetic Resonance Centre,
Department of Physics, Nottingham University, Nottingham, United
Kingdom NG7 2RD
This study investigated the variation in
magnetic resonance characteristics of the fetal liver during a time of
changing erythropoietic function. Echo-planar imaging was carried out
in 25 normal pregnant women at 20 and 26 wk gestation. The signal
intensity from regions of the fetal liver, background image, and
maternal back muscle and the highest signal intensity from the maternal
spinal cord were measured and compared with the signal intensity of
amniotic fluid. Data are expressed as ratios, in arbitrary units
(median pixel values; interquartile range shown in parentheses), and
analyzed with the use of Wilcoxon's signed-rank test. At 20 wk, the
signal intensity ratio of liver to amniotic fluid was 0.309 (0.231-0.365). At 26 wk, the ratio was 0.544 (0.429-0.616).
The change was highly significant (P < 0.0001). No change in the signal intensity ratios of amniotic fluid
compared with other measured parameters was noted. These data are
consistent with known changes in fetal liver erythropoiesis occurring
between 20 and 26 wk gestation and have potential use in early
noninvasive physiological assessment of the fetus.
hematopoiesis; noninvasive fetal assessment
