Korean J Perinatol.  2007 Jun;18(2):131-140.

Evaluation of the Antenatal Fetal Brain Metabolites using Proton Magnetic Resonance Spectroscopy

• Ma JY
• Won HS
• Kim JK
• Kim SR
• Shim JY
• Lee PR
• Kim A

Abstract

OBJECTIVE
The purpose of this study was to compare the sensitivity of proton Magnetic Resonance Spectrography (MRS) for estimating absolute metabolite concentrations and ratio of fetal brains.
METHODS
Between September 2005 and August 2006, our study was prospective single center trial and included 39 healthy women (Group 1: fetuses with risk factor of fetal distress or hypoxic damage [n=15], Group 2: fetal CNS anomalies on ultrasound [n=12], Group 3: normal fetuses [n=12]). We quantified resonances for the main proton MRS-detectable brain and calculated metabolite ratios of the three groups. We compared the obtained metabolite levels of the three groups with electronic fetal cardiotocography, Doppler ultrasound examination, Apgar score, and umbilical artery blood gas analysis.
RESULTS
Abnormal amniotic fluid, abnormal Doppler studies, and abnormal cardiotocograms were significantly more prevalent in Group 1 compared with those of Group 2 and 3. In Group 1, choline (Cho) levels (7.86+/-3.51mmol/L) were significantly higher than in Group 2 or 3 (p=0.024). The ratios of N-acetylasparate (NAA)/creatinine-phosphocreatine (Cr) and Cho/Cr were increased whereas the ratios of NAA/Cho, lactate (Lac)/Cho, Lac/NAA, and Lac/Cr were decreased; however, there was no statistical significance. In patients who have oligohydramnios and absence of umbilical diastolic flow, choline and N-acetylasparate levels were significantly elevated (p<0.05, p<0.05, respectively). But, MRS metabolites and ratios showed no significant differences for low Apgar scores, umbilical arterial academia, uterine artery notching, maternal blood pressure or abnormal fetal cardiotocograms.
CONCLUSION
This study demonstrates the possibility of performing proton MRS to assess the metabolic information of the fetal brain. Further technical progress may be useful of improving the degree of detection of hypoxic changes or an impending hypoxic state for prenatal diagnosis.

Keyword

Proton MR spectroscopy; Hypoxic injury; Fetal brain; Prenatal test

MeSH Terms

Amniotic Fluid
Apgar Score
Blood Gas Analysis
Blood Pressure
Brain*
Cardiotocography
Choline
Female
Fetal Distress
Fetus
Humans
Lactic Acid
Magnetic Resonance Spectroscopy*
Oligohydramnios
Pregnancy
Prenatal Diagnosis
Prospective Studies
Protons*
Risk Factors
Ultrasonography
Umbilical Arteries
Uterine Artery
Choline
Lactic Acid
Protons