Relationship between Doppler findings and fetal brain apparent diffusion coefficient in early-onset intra-uterine growth restriction .

OBJECTIVE: The aim of the study is to assess the relationship between uteroplacental Doppler sonography findings and cerebral diffusion measured by diffusion-weighted magnetic resonance imaging (DWI) in fetuses with early-onset intrauterine growth restriction (IUGR).

MATERIALS AND METHODS: The study included 54 pregnant women with fetal IUGR and 15 healthy controls (n: 15). Fetuses with IUGR were classified into four groups based on Doppler findings: group 1 (n = 12), umbilical artery (UA) pulsatility index (PI) > 95pc; group 2 (n = 11), UA PI >95 pc and middle cerebral artery PI < 5pc; group 3 (n = 21), absent end-diastolic (A-EDF) in UA; group 4 (n = 10), reversed EDF in UA. After Doppler evaluation, DWI was performed in all patients within hours. The groups were compared with respect to apparent diffusion coefficient (ADC) levels.

FINDINGS: In cases with fetal IUGR, significant decreases were detected in ADC values of periatrial white matter (PAWM) (p = .01), frontal white matter (FWM) (p = .038), thalamus (p = .004), and basal ganglia (p = .013) compared to controls. In Doppler subgroup analysis adjusted for gestational age, ADC values of FWM, thalami, and pons were significantly lower in group 4 than control group (p = .02, p = .02, and p = .037, respectively). In PAWM, ADC values were significantly lower in group 4 than control and Group 1 (p = .004). No significant differences with regard to ADC values in basal ganglia, cerebellum was found between Doppler groups and control.

CONCLUSIONS: In fetuses with IUGR, ADC values as measured by DWI decreases. The critical Doppler finding that is associated with reduced diffusion in some brain areas (FWM, PAWM, thalami, pons) is reverse end-diastolic flow in umbilical artery. Further prospective studies with larger sample size are needed to introduce cerebral ADC values in the management of IUGR.