[Reversible primary empty sella. Case report].

We report the case of a 13-year-old girl with an increased hypophysis that mimicked an adenoma, who developed a partial empty sella on MRI after an acute episode of hydrocephalus. After replacement of a CSF shunt, the intracranial pressure returned to normal and the hypophysis filled up again all the sellar fossa. We discuss the possibility of the involvement by an ischemic atrophy of the adenohypophysis in the development of a primary empty sella with idiopathic chronic raised intracranial pressure that prevents the recovery of the gland volume after restoring the intracranial pressure to normal values. Restitution of empty sella may be an indicator of normal intracranial pressure in these cases.