Septo-optic dysplasia plus: A case report for reviewing and recognizing this condition

Septo-optic dysplasia is a congenital neurological condition with multifactorial etiology, characterized by septum pellucidum agenesis and/or corpus callosum dysgenesis, hypoplasia of the chiasm or optic nerves, and hormonal dysfunction with pituitary or hypothalamic alterations. Diagnosis requires two of these criteria and magnetic resonance is the imaging test of choice. Most cases present with abnormalities of cortical development in the form known as septo-optic dysplasia plus. While seizures and neurodevelopmental disorders are the dominant neurological manifestations, this entity is highly heterogeneous and has multiple clinical and radiological findings to consider. We present the case of a 35-year-old man with a history of cranioencephalic trauma in childhood and remission for refractory focal epilepsy associated with cognitive deficit. During the initial examination, the simple cranial tomography showed septum pellucidum agenesis and corpus callosum dysgenesis. Brain magnetic resonance imaging revealed agenesis of the septum pellucidum, irregularity and anomalous thickening of the cerebral cortex in frontal lobes and perisylvian region, heterotopic gray matter in frontal lobes and left fronto-insular region, mild supratentorial ventriculomegaly, atypical appearance of the corpus callosum rostrum, and hypoplasia of the chiasm and optic nerves. Although agenesis of the septum pellucidum was the key finding in this case, it is not present in all patients. The relevance of magnetic resonance imaging for the detailed evaluation of other involved structures, highlighting optic nerve hypoplasia, is fundamental in the radiologist's diagnostic workup and this entity recognition.