Feasibility of magnetic resonance spectroscopy for evaluating fetal lung maturity.
OBJECTIVE
Amniocentesis is an invasive procedure with inherent risks. Magnetic resonance (MR) spectroscopy is a safe noninvasive way of measuring levels of choline-containing compounds (including surfactant) and other metabolites. The purpose of this study was to test the feasibility of assessing fetal lung maturity in vivo and ex vivo using MR spectroscopy to determine differences in amniotic fluid choline concentrations between the second and third trimesters.


METHODS
Magnetic resonance spectroscopy was performed on ex vivo samples of amniotic fluid from second- and third-trimester fetuses. In vivo MR spectroscopy was performed on amniotic fluid and fetal lungs in third-trimester fetuses. Spectral acquisition and analysis were performed by an attending radiologist in conjunction with an MR spectroscopist.


RESULTS
Choline-containing compounds were observed from 3.20 to 3.25 ppm. Comparison of spectra from second- and third-trimester amniocentesis revealed a trend toward increased choline at later gestational ages. Spectra from amniotic fluid and lungs of a third-trimester fetus showed that choline can be detected in the in vivo setting.


CONCLUSIONS
Magnetic resonance spectroscopy is a safe noninvasive procedure that enables measurement of choline-containing compounds in fetal lung and amniotic fluid. Magnetic resonance spectroscopy shows a trend toward an increased quantity of choline in third- vs second-trimester amniocentesis.
Clifton
Matthew S
MS
Department of Surgery, University of California-San Francisco, San Francisco, CA 94143-0570, USA.
Joe
Bonnie N
BN
Zektzer
Andrew S
AS
Kurhanewicz
John
J
Vigneron
Daniel B
DB
Coakley
Fergus V
FV
Nobuhara
Kerilyn K
KK
Swanson
Mark G
MG
D000653:Amniotic Fluid / Q000737:chemistry*; D002794:Choline / Q000032:analysis*; D005240:Feasibility Studies; D005325:Fetal Organ Maturity; D006801:Humans; D008168:Lung / Q000196:embryology*; D009682:Magnetic Resonance Spectroscopy
D002794:Choline