Diastematobulbia type II without associated dermoid tumor: case report.

Split cord malformation (SCM) is a term used for all double spinal cords. It represents 3.8%-5% of spinal dysraphisms. Pang et al.'s embryological theory proposes the formation of an "accessory neurenteric canal" that communicates with the yolk sac and amnion. To the authors' knowledge, only three cases of diastematobulbia (basicranial SCM) associated with a spur or dermoid have been reported in the literature.The case patient is a newborn girl with an occipitocervical meningocele and dermal sinus associated with an anomaly of notochordal development in the transition between the medulla oblongata and the spinal cord (diastematobulbia) without a bony septum or dermoid cyst. The patient also has agenesis of the atlas and an absence of corticospinal tract decussation. This patient underwent reconstruction of the occipital meningocele and dermal sinus excision.To the authors' knowledge, this is the first described case of type II diastematobulbia (basicranial SCM), without a dermoid cyst. The authors analyzed the embryological errors present in the case patient and considered the option of further surgical treatment depending on the evolution of the patient's condition. At the time of this report, the patient had shown normal psychomotor development. However, this fact may only be due to the patient's young age. Considering that after initial untethering the patient remained clinically asymptomatic, conservative and close surveillance has been and continues to be the proposed treatment.