Impact of Intrauterine Growth Restriction on Fetal Cortical Brain  Development: A Neurosonographic Assessment at 28-36 Weeks of Gestation

Behrokh  Sahebdel; Reihaneh Mortazavi  Ardestani; Setareh  Soltani; Mohammad Hossein  Golezar; Fatemeh   Golshahi; Nafiseh  Saedi; Fatemeh Rahimi  Sharbaf; Mahboobeh  Shirazi; Nooshin  Faraji; Mohadese  Dashtkoohi; Zohreh  Heidary; Masoumeh  Aslanpour

doi:10.18502/jri.v26i2.19432

Behrokh Sahebdel Department of Obstetrics and Gynecology, Fetal an d Neonatal Research Center, Yas Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
Reihaneh Mortazavi Ardestani Department of Radiology, Tehran University of Medical Sciences, Tehran, Iran
Setareh Soltani Clinical Research Development Center, Taleghani and Imam Ali Hospital, Kermanshah University of Medical Sciences, Kermanshah, Iran
Mohammad Hossein Golezar Advanced Diagnostic and Interventional Radiology Research Center (ADIR), Medical Imaging Center, Tehran University of Medical Sciences, Tehran, Iran
Fatemeh Golshahi Department of Obstetrics and Gynecology, Fetal an d Neonatal Research Center, Yas Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
Nafiseh Saedi Department of Obstetrics and Gynecology, Fetal an d Neonatal Research Center, Yas Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
Fatemeh Rahimi Sharbaf Department of Obstetrics and Gynecology, Fetal an d Neonatal Research Center, Yas Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
Mahboobeh Shirazi Department of Obstetrics and Gynecology, Fetal an d Neonatal Research Center, Yas Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
Nooshin Faraji Department of Obstetrics and Gynecology, Fetal an d Neonatal Research Center, Yas Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
Mohadese Dashtkoohi Vali-E-Asr Reproductive Health Research Center, Family Health Research Institute, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
Zohreh Heidary Vali-E-Asr Reproductive Health Research Center, Family Health Research Institute, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
Masoumeh Aslanpour Department of Obstetrics and Gynecology, Fetal an d Neonatal Research Center, Yas Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran

DOI: https://doi.org/10.18502/jri.v26i2.19432

Keywords: Cortical maturation, Fetal brain development, Fetal ultrasound, Insula, Intra-uterine growth restriction, Neurosonography, Nomogram, Sylvian fissure

Abstract

Background: Cortical folding during fetal brain development reflects neural matur-ation. Fetal growth restriction (FGR) may disrupt this process, potentially affecting neurodevelopmental outcomes. Although ultrasound enables noninvasive sulcal assessment, so normative data and objective tools are lacking. The purpose of the current study was to assess the impact of FGR on fetal cortical development using neurosonography and establish a third-trimester nomogram for cortical maturation.

Methods: This prospective study included 425 singleton pregnancies (330 appropri-ate-for-gestational-age [AGA], 54 symmetrical FGR, and 41 asymmetrical FGR) at 28–36 weeks. Conducted at a Tehran tertiary center (2023–2024), the study included cases with normal anatomy and negative aneuploidy screening. Neurosonographic parameters including Sylvian fissure (SF), insula, parieto-occipital fissure (POF), cavum septum pellucidum (CSP) width, and ventricular diameter were measured and the ratios calculated relative to biparietal diameter (BPD). ANOVA and post-hoc tests were applied and statistical significance was set at p<0.05.

Results: No significant differences in neurosonographic ratios (e.g., SF/Insula, POF/ BPD, CSPW/BPD) were found between AGA and FGR groups. However, unadjust-ed SF and insular depths were reduced in symmetrical FGR fetuses with head cir-cumference (HC) <10th percentile. Asymmetrical FGR showed no differences. A gestational-age-based nomogram was developed for AGA fetuses.

Conclusion: While absolute sulcal measurements vary with head size in FGR, biometric adjustments (e.g., BPD ratios) improve cortical maturation assessment. The study supports ratio-based neurosonography and provides normative data for objective fetal brain evaluation.