Vanishing brain space-occupying lesion in a child: illustrative case.

BACKGROUND: Vanishing brain space-occupying lesions are rare clinical entities characterized by spontaneous regression of intracranial lesions before definitive diagnosis. They may mimic neoplastic or infective conditions, creating diagnostic uncertainty. OBSERVATIONS: A 14-year-old boy presented with recurrent complex partial seizures associated with postictal sleep. MRI demonstrated a left parietal intra-axial ring-enhancing lesion with surrounding vasogenic edema. The patient was started on a regimen of oral carbamazepine 200 mg twice daily, and he was scheduled for surgical excision, but his family declined because of financial constraints. Thirteen months later, repeat imaging revealed complete spontaneous resolution of the lesion and edema without medical or surgical intervention. LESSONS: This case highlights the importance of careful clinical and radiological evaluation in children presenting with solitary ring-enhancing lesions. Some lesions may resolve spontaneously, particularly infective or inflammatory lesions, and unnecessary surgery may therefore be avoided. https://thejns.org/doi/10.3171/CASE26532.