Abstract
Introduction: Prenatal imaging is crucial for evaluating neurological development in cases of absence of septum pellucidum (ASP), which may be associated with a spectrum of cortical, cerebellar and ocular anomalies and variable neurodevelopmental outcomes. Recent advances in fetal MRI techniques have improved the detection and characterization of subtle brain abnormalities. Case report: A pregnant patient was referred to our tertiary centre for targeted neurosonography at 28weeks of gestation, confirming ASP initially considered isolated. Fetal MRI at 33 weeks suspected associated cortical malformations, with unilateral peri-sylvian polymicrogyria and closed lip schizencephaly, but it partially limited by motion artefacts. Subsequent super‑resolution reconstruction (SRR) and cortical surface extraction confirmed the presence of polymicrogyria associated with schizencephaly. Post-MRI neurosonography also confirmed unilateral perisylvian polymicrogyria and schizencephaly. Following multidisciplinary discussion parents opted for termination of pregnancy. Post‑mortem neuropathological examination confirmed the imaging findings, demonstrating polymicrogyria associated with schizencephaly in the right perisylvian region. Conclusion: This case highlights the possible added diagnostic value of advanced fetal MRI post‑processing, which enabled precise characterization of cortical abnormalities not confidently identified on conventional imaging. The strong correlation with neuropathological findings supports the potential role of surface‑based analysis in improving diagnostic accuracy and prenatal counselling in cases of ASP.