Apparent Diffusion Coefficient Value Changes and Clinical Correlation in 90 Cases of Cytomegalovirus-Infected Fetuses with Unremarkable Fetal MRI Results

Abstract

Cytomegalovirus infection causes diffuse reduction in ADC values in the fetal brain even in unremarkable fetal MR imaging scans. Cytomegalovirus-infected children with unremarkable fetal MR imaging scans do not deviate from the healthy population in the VABS-II neurocognitive assessment. ADC values were not correlated with VABS-II scores. However, the lack of clinical findings, as seen in most cytomegalovirus-infected fetuses, does not eliminate the possibility of future neurodevelopmental pathology.

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 …”

“…The five-point DWI protocol was adapted from the earlier adult brain study 30 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. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] An MPF mapping protocol was implemented as described previously 20,21 based on a 3D spoiled fast field-echo (FFE) sequence and included the following scans: MT-weighted with TR = 32 msec, flip angle (FA) = 8 and an off-resonance saturation pulse; reference with the same parameters and without the saturation pulse; T 1 -weighted with TR = 20 msec and FA = 20 ; and proton-density (PD)-weighted with TR = 20 msec and FA = 4 . All source images for MPF mapping were acquired with multishot EPI readout (acceleration factor 9); TE = 6.3 msec; 3D FOV 25 × 25 × 6 cm 3 ; matrix 168 × 167 × 12 (interpolated to 320 × 320 × 24); voxel size 1.49 × 1.50 × 5.0 mm 3 (interpolated to 0.78 × 0.78 × 2.50 mm 3 ); and two signal averages.…”

“…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.…”