DERMOID CYST OF THE ANTERIOR FONTANELLE IN A CHILD: MRI-Guided Neurosurgical Management and Histopathological Confirmation

Masses arising from the anterior fontanelle in children require a systematic diagnostic approach to rule out intracranial communication and to ensure safe surgical planning. We report the case of a 3-year-old boy, born at term by vaginal delivery, with normal psychomotor development and no neurological deficit, presenting with a slowly enlarging midline extracranial mass over the anterior fontanelle for approximately 3 years. Clinical examination showed a 5–6 cm lesion with a broad implantation base, covered by intact, non-inflamed skin. Initial computed tomography (CT) demonstrated a well-circumscribed subcutaneous, fluid-density cystic lesion (55 × 45 mm) without associated intracranial abnormalities. Subsequent contrast-enhanced brain magnetic resonance imaging (MRI) identified a well-defined midline anterior subgaleal cystic lesion (49 × 26 × 52 mm), without enhancement and with no detectable intracranial communication, consistent with an anterior fontanelle inclusion cyst . Complete excision in a single specimen was achieved, with subsequent coagulation of the implantation base. Histopathological analysis confirmed a dermoid cyst. 

Keywords: anterior fontanelle; dermoid cyst; inclusion cyst; MRI; pediatric neurosurgery; histopathology.