Assessment of normal fetal brain maturation in utero by proton magnetic resonance spectroscopy.
Cerebral maturation in the normal human fetal brain was investigated by in utero localized proton MR spectroscopy ((1)H MRS). Fifty-eight subjects at 22-39 weeks of gestational age (GA) were explored. A combination of anterior body phased-array coils (four elements) and posterior spinal coils (two to three elements) was used. Four sequences were performed (point-resolved spectroscopy (PRESS) sequence with short and long TEs (30 and 135 ms), with and without water saturation). A significant reduction in myo-inositol (myo-Ins) and choline (Cho) levels, and an increase in N-acetylaspartate (NAA) and creatine (Cr) content were observed with progressing age. A new finding is the detection of NAA as early as 22 weeks of GA. This result is probably related to the fact that oligodendrocytes (whether mature or not) express NAA, as demonstrated by in vitro studies. Cho and myo-inositol were the predominant resonances from 22 to 30 weeks and decreased gradually, probably reflecting the variations in substrate needed for membrane synthesis and myelination. The normal MRS data for the second trimester of gestation (when fetal MRI is usually performed) reported here can help determine whether brain metabolism is altered or not, especially when subtle anatomic changes are observed on conventional images.
Girard
Nadine
N
Service de Neuroradiologie, Assistance Publique-Hôpitaux de Marseille, Hôpital la Timone, Université de la Méditerranée, Marseille, France. nadine.girard@ap-hm.fr
Gouny
Sylviane Confort
SC
Viola
Angèle
A
Le Fur
Yann
Y
Viout
Patrick
P
Chaumoitre
Kathia
K
D'Ercole
Claude
C
Gire
Catherine
C
Figarella-Branger
Dominique
D
Cozzone
Patrick J
PJ
D000375:Aging / Q000502:physiology; D000465:Algorithms; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001921:Brain / Q000196:embryology* / Q000378:metabolism; D001923:Brain Chemistry; D005260:Female; D047109:Fetal Development / Q000502:physiology*; D005865:Gestational Age; D006801:Humans; D016014:Linear Models; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D011247:Pregnancy
D001224:Aspartic Acid; C000179:N-acetylaspartate