Unexpected delayed idiopathic intracranial hypertension following minor pediatric traumatic brain injury: Case report and literature review

Background: Idiopathic intracranial hypertension (IIH) is characterized by elevated intracranial pressure (ICP) without an identifiable intracranial lesion, hydrocephalus, vascular abnormality, or central nervous system infection. Although several pediatric risk factors have been described, including medications, endocrine disorders, autoimmune diseases, anemia, and cerebral venous outflow abnormalities, IIH occurring after traumatic brain injury (TBI) is exceptionally rare. Case Description: A 10-year-old girl developed progressive headache, vomiting, diplopia, and visual impairment 3 weeks after a mild TBI. Neurological examination revealed bilateral sixth cranial nerve palsy, and fundus examination demonstrated Grade III papilledema. Brain magnetic resonance imaging showed indirect signs of intracranial hypertension without structural lesions or cerebral venous sinus thrombosis. Lumbar puncture confirmed elevated cerebrospinal fluid (CSF) opening pressure with normal CSF composition, establishing the diagnosis of IIH. The patient was treated with acetazolamide and serial therapeutic lumbar punctures, resulting in complete clinical and ophthalmological recovery. Conclusion: Posttraumatic IIH is a rare but potentially vision-threatening complication of mild pediatric TBI. Delayed onset of symptoms may obscure the diagnosis. Early recognition, exclusion of secondary causes, and prompt treatment are essential to preserve vision and achieve favorable outcomes. This case adds to the limited literature on pediatric posttraumatic IIH and emphasizes the importance of considering IIH in children presenting with delayed signs of raised ICP after head trauma.