Unusual Intraparenchymal Pontomedullary Epidermoid Cyst in a 2-Year-Old Child: A Case Report and Review of the Literature

Abstract

Background: Intrinsic brainstem epidermoid cysts are rare, benign, slow-growing lesions. Their eloquence precludes complete excision; however, subtotal resection often will result in prolonged or sometimes permanent relief of presenting symptoms and signs. We describe an unusual case and review the literature of this pathology in the pediatric population.

Case description: We report an intra-axial pontine epidermoid cyst in a 2-year-old girl who presented with developmental delay, multiple cranial nerve palsies, and pneumonia. Magnetic resonance imaging demonstrated an intrinsic pontine lesion with partial restricted diffusion and an enhancing plaque, the latter not typically seen in congenital lesions like epidermoid. However, gross surgical inspection and histopathology confirmed an epidermoid.

Conclusions: Our case, supported by the literature, shows that brain stem epidermoid cysts may have atypical radiologic characteristics and that near-total resection remains safe and can improve outcome.

Keywords: Brainstem; Congenital; Cranial nerves; Epidermoid; Intra-axial; Pons.