Brain Metabolite Differences in Fetuses With Cytomegalovirus Infection: A Magnetic Resonance Spectroscopy Study.

Area of Science:

• Neuroimaging
• Fetal Medicine
• Infectious Diseases

Background:

• Cytomegalovirus (CMV) is a common intrauterine infection with potential adverse fetal outcomes.
• Brain abnormalities on fetal MRI may not always predict clinical significance.
• Normal fetal development cannot be assumed even with a normal MRI in CMV-infected fetuses.

Purpose of the Study:

• To investigate brain metabolite differences in fetuses infected with CMV using magnetic resonance spectroscopy (MRS).
• To assess the utility of MRS in detecting subtle brain damage in CMV-infected fetuses.

Main Methods:

• Retrospective analysis of 44 CMV-infected fetuses and 9 uninfected controls.
• Categorization of infected fetuses into groups based on MRI findings: gross abnormalities, subtle white matter hyperintensities (WMHS), or normal MRI.
• Magnetic resonance spectroscopy (MRS) acquired at 3T to analyze metabolite ratios (tNAA/tCr) in the basal ganglia.

Main Results:

• MRS was successfully acquired in 63% of fetuses.
• Significantly reduced tNAA/tCr ratios were observed in CMV-infected fetuses with gross MRI abnormalities compared to other groups.
• No significant metabolic differences were detected by MRS in CMV-infected fetuses with isolated WMHS or normal MRI.

Conclusions:

• Reduced tNAA/tCr in apparently normal brain tissue indicates extensive damage in fetuses with gross brain abnormalities due to CMV.
• MRS did not detect detectable brain damage in CMV-infected fetuses with isolated white matter hyperintensities (WMHS).
• MRS may aid in assessing the extent of brain damage in congenital CMV infection.