Purpose: This study aimed to compare the apparent diffusion coefficient (ADC) values of different brain areas between two groups of intrauterine growth restricted (IUGR) foetuses and control cases. Material and methods: A total of 38 foetuses with IUGR and 18 normal control foetuses with similar gestational age were compared using a 3T magnetic resonance scanner. IUGR cases included 23 foetuses with clinical severity signs (group A) and 15 foetuses without clinical severity signs (group B). ADC values were measured in different brain regions and compared among groups. Foetuses with structural brain abnormalities were excluded from the study. Results: All foetuses had normal foetal structural brain anatomy. Head circumference (HC) < 5% was more common in IUGR group A compared to IUGR group B (56.5% vs. 13.3%, p < 0.0001). In comparison to the normal group, the ADC values in IUGR foetuses were significantly lower in cerebellar hemispheres (CH) (1.239 vs. 1.280.5 × 10-3 mm 2 /s, p = 0.045), thalami (1.205 vs. 1.285 × 10-3 mm 2 /s, p = 0.031) and caudate nucleus (CN) (1.319 vs. 1.394 × 10-3 mm 2 /s, p = 0.04). However, there were no significant differences in ADC values between IUGR subtypes. Among all brain regions, pons had the lowest ADC values. Conclusions: ADC values of thalami, CN, and CH were significantly lower in IUGR than control foetuses, while there was no significant difference among IUGR groups. Further studies are needed to evaluate the prognostic value of ADC changes in IUGR foetuses.

Background: Intrauterine growth restriction (IUGR) is a major factor in long-term perinatal morbidity and is associated with abnormal fetal brain development; however, its pattern of brain involvement remains unknown. Objectives: This study aimed to investigate the effect of IUGR on the brain parenchyma. Methods: Forty-two women with IUGR pregnancy and 28 women with normally grown fetuses at 28 - 38 weeks of pregnancy underwent 3-tesla magnetic resonance imaging (MRI). Cortical thickness was assessed in four regions and corrected by the biparietal diameter/2. Also, the whole brain surface area (WBA) was measured, and the areas of six brain regions were calculated and corrected by WBA. Results: In the IUGR group, the cortical thickness in the insula and temporal lobe was significantly thinner than the control group (0.034 vs. 0.043 and 0.036 vs. 0.047, respectively; P < 0.05); these fetuses also showed significantly reduced WBA (P = 0.028). The corrected brain areas were not significantly different between the groups, except for the corrected areas of the cerebellum and the hippocampus, which increased in the IUGR group as compared to the control group (0.147 vs. 0.130 and 0.017 vs. 0.0125, respectively; P < 0.05). Conclusions: In the IUGR fetuses, significantly thinner insular cortex and temporal lobe cortex and smaller WBA were found compared to the control group. Among different brain regions, the cerebellum and the hippocampus were less affected by growth restriction in the antenatal period.