Two-stage surgical intervention for a rare case of intersected nasoethmoidal encephalocele and open-lip schizencephaly in an infant: illustrative case.

backgroundSchizencephaly and encephaloceles are rare developmental birth defects, with the former involving abnormal clefts in the cerebral hemispheres connected to the ventricular system and the latter involving a neural tube defect characterized by the protrusion of brain tissue through an abnormal skull opening. These conditions are individually uncommon, and their simultaneous occurrence in a single patient is exceedingly unusual. OBSERVATIONS: This case report explores the intersection of these two rare congenital malformations in a 2-month-old female patient from an indigenous community in a rural area of Colombia. She presented with open-lip schizencephaly accompanied by a nasoethmoidal encephalocele and additional brain abnormalities, including septum pellucidum agenesis, corpus callosum dysgenesis, and a suspected bilateral optic nerve hypoplasia. LESSONS: Management involved a two-step surgical procedure, addressing hydrocephalus with a ventriculoperitoneal shunt and the encephalocele with posterior excision, thereby facilitating optimal cortical gray matter development and enhancing neurological outcomes. https://thejns.org/doi/10.3171/CASE24259.