The headband that held in the brain: illustrative case.

backgroundA 45-year-old woman with a history of schizoaffective disorder presented to the emergency department from a skilled nursing facility after being found unconscious in the bathroom with active scalp bleeding from a circumferential wound. The neurosurgery team was consulted due to concerns of intracranial infection. OBSERVATIONS: CT of the head revealed band-like circumferential bony erosion of the calvarium traversing the superior sagittal sinus. Family members denied any history of prior neurosurgical intervention or cranial deformity; however, they noted a fall approximately 7 months prior that resulted in a scalp wound. The patient was taken to the operating room for surgical exploration, where a constrictive cloth embedded within the scalp was identified as the source of the circumferential skull injury and was completely removed. LESSONS: This case report highlights a rare and unusual cause of skull injury resulting from external constriction over several weeks. Surgeons should maintain awareness of atraumatic causes of skull injury, particularly in patients with severe mental illness and complex social circumstances who experience disproportionate medical morbidity and often encounter fragmented or delayed care. Early imaging, neurosurgical evaluation, and coordinated multidisciplinary care are necessary to prevent potentially catastrophic intracranial complications. https://thejns.org/doi/10.3171/CASE26651.