A Novel Management Proposal for Intrinsic Brainstem Neurenteric Cysts: Case Report

Neurenteric cysts (NCs) are rare congenital lesions with epithelial mucin-secreting walls. They can occur anywhere along the neural axis, and an intrinsic midbrain cyst is extraordinary. Surgical management may pose a challenge due to the location of the lesion and adhesion of the cyst wall to the surrounding brainstem. The authors describe the first case of pediatric NC that was treated successfully with intracystic interferon-α (IFN-α).A 16-month-old baby girl presented with a 2-week history of progressive croup, vomiting, and swallowing difficulty. MRI revealed a 1.8-cm cystic intrinsic lesion in the pontomedullary region. She initially underwent posterior fossa craniotomy and drainage of the cyst under intraoperative neurophysiology monitoring. Three weeks following the procedure, her symptoms recurred, and follow-up MRI demonstrated cystic recurrence. She underwent repeat aspiration of the cyst and biopsy of the cyst wall, and INF-α-2b was injected into the cystic cavity. Her symptoms improved and completely resolved after 5 months. A 9-month follow-up brain MRI study showed complete resolution of the NC. Intracystic IFN-α injection after cystic content aspiration may be a safe treatment option for the management of intrinsic brainstem NCs. Long-term clinical and radiological follow-up is recommended.