[Idiopathic intracranial hypertension in a patient with Chiari I malformation].

CASE REPORT The case involves a 22-year-old woman who presented with headache and decreased vision. She showed asymmetric papilledema, and a 6-mm tonsillar descent was observed in the image tests. She was diagnosed with secondary intracranial hypertension coinciding with the symptoms of a Chiari malformation (MC). DISCUSSION Chiari malformation type I is the most common in this group of malformations, and is characterized by a greater than 5mm descent of the tonsils, being able to cause increased intracranial pressure and papilledema by blocking the flow of the cerebrospinal fluid. In this case, the MC was not the responsible for triggering the secondary intracranial hypertension, but a mere coincidence of both processes.