- In the right clinical context, decreased visual acuity + papilledema = BAD. These patients need workup including LP and MRI in the ED, and urgent referral to ophthalmology (for optic nerve sheath fenestration) or neurosurgery (for shunt placement).
- Papilledema can be difficult to recognize. Beware of mimics such as optic nerve head drusen and decreased optic disc height.
- LP is essential in the workup of IIH, but is limited by many potential confounders. To maximize accuracy in obtaining an opening pressure reading, remember la clé (French for "the KEY")- Calm patient, Lateral decubitus position, knees Extended