Acrania: an extremely rare congenital malformation and the first surviving case report of cranioschisis

Abstract Background Acrania, also known as acalvaria, is an extremely rare congenital malformation characterized by the absence of calvarial bone structures and defects in the associated muscles and sometimes dural structures, while the skull base and facial bone structure are normal. Case presentation We present the case of a baby born vaginally at 38 weeks of gestation to a 31-year-old mother with an Apgar score of 9–10. Prenatal tests had identified the risk of severe congenital malformation, but the mother refused the option of pregnancy termination. The baby was born with a severe scalp defect and external herniation of immature brain tissue. On the 9th postnatal day, the immature brain tissue was excised, and the defective scalp was repaired. Following the development of hydrocephalus during follow-up, a ventriculoperitoneal shunt was placed at 5 months. The patient remains under uneventful outpatient follow-up at 6 years of age, with persistent neuromotor developmental delay. Conclusions Acrania was previously known to be a pathology incompatible with life, but the number of survivors is increasing now owing to advancements in medical interventions. Further medical research on this topic will help uncover more information regarding the pathophysiology and treatment of this disease.