Region-specific reductions in brain apparent diffusion coefficient in cytomegalovirus-infected fetuses

Abstract

Objective To evaluate the effects of cytomegalovirus (CMV) infection on apparent diffusion coefficient (ADC) values of the fetal brain in utero.Methods In this retrospective analysis we compared 58 fetal head magnetic resonance imaging (fhMRI) scans of PCR-verified CMV-infected fetuses, obtained in 2008-2012

Direct comparison between apparent diffusion coefficient and macromolecular proton fraction as quantitative biomarkers of the human fetal brain maturation

“…More research is needed to precisely assess the accuracy of MPF measurements in clinical MRI settings using unmodified manufacturers' sequences. It also should be noted in this context that the literature fetal brain ADC values vary widely depending on the imaging equipment and protocol. For example, mean ADC in fetal frontal WM were reported in a range from 1370–2170 × 10 ‐6 mm 2 /s .…”

“…For ADC mapping, a 2D single‐shot spin‐echo diffusion‐weighted echo‐planar imaging (EPI) sequence was used with the following parameters: repetition time / echo time (TR/TE) = 2940/64 msec; three orthogonal diffusion directions; five b‐values of 0, 125, 251, 376, and 501 s/mm 2 ; field of view (FOV) 29 × 29 cm 2 ; matrix 144 × 123 (interpolated to 240 × 240); in‐plane resolution 2.01 × 2.36 mm 2 (interpolated to 1.21 × 1.21 mm 2 ); 12 slices with thickness of 5 mm and gap of 0.4 mm; two signal averages; and scan time of 79 seconds. The five‐point DWI protocol was adapted from the earlier adult brain study with a 2‐fold reduction of the b‐values in view of the fact that ADC values in the fetal brain are 2–3‐fold larger as compared with the adult brain …”

“…MAGNETIC RESONANCE IMAGING (MRI) techniques for quantitative assessment of the fetal brain tissue maturation may facilitate a new approach in the early diagnosis of various prenatal brain diseases and injuries and provide fundamental knowledge about mechanisms of pre‐ and postnatal neurodevelopment. Among these techniques, diffusion‐weighted imaging (DWI) has attracted significant interest over the past decade due to its high sensitivity to the fetal brain tissue changes during pregnancy, broad availability, and rapid data acquisition that is critical for fetal MRI examinations . Numerous studies demonstrated significant correlations of the apparent diffusion coefficient (ADC) with gestational age (GA) in various brain anatomical structures and sensitivity of ADC to certain fetal pathological conditions including ischemia, intrauterine growth restriction, ventriculomegaly, Chiari malformation, and cytomegalovirus infection …”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] Numerous studies demonstrated significant correlations of the apparent diffusion coefficient (ADC) with gestational age (GA) in various brain anatomical structures [1][2][3][4][5][6][7][8] and sensitivity of ADC to certain fetal pathological conditions including ischemia, 9,10 intrauterine growth restriction, 11,12 ventriculomegaly, 13,14 Chiari malformation, 15 and cytomegalovirus infection. 16,17 A newer quantitative MRI method, fast macromolecular proton fraction (MPF) mapping, 18,19 has been recently adapted to fetal brain applications. 20,21 MPF has been histologically validated as a myelin biomarker in animal models [22][23][24][25] and has shown the capability to quantify myelin damage in clinical studies of multiple sclerosis 26,27 and mild traumatic brain injury.…”

Fetal MRI: A technical update with educational aspirations

“…The importance of such an assessment in fetal brain MRI is obvious and several attempts have been made to perform fetal brain diffusion imaging (101–113). The inherent sensitivity to all motion, however, generally means that successful fetal diffusion brain imaging is primarily demonstrated in fetuses with pelvic head engagement (104) or in fetuses with low fetal activity due to the use of maternal sedation (110).…”