Which condition requires the head of the backboard to be elevated to decrease intraocular pressure?

Hyphema is a condition characterized by the presence of blood in the anterior chamber of the eye, typically due to trauma. When managing a patient with hyphema, it is crucial to minimize intraocular pressure to prevent further damage to the eye and preserve vision. Elevating the head of the backboard helps reduce intraocular pressure by allowing better venous drainage from the eye and decreasing the buildup of fluid in the anterior chamber.

In contrast, while glaucoma does involve increased intraocular pressure, the management strategies differ significantly from those used for hyphema, and simply elevating the head is not typically indicated for glaucoma. Retinal detachment requires positioning that can often involve keeping the affected eye downward, depending on the type of detachment, and does not specifically benefit from head elevation to reduce pressure. Otitis externa is an outer ear infection and is unrelated to intraocular pressure concerns at all. Thus, hyphema is the condition that specifically necessitates head elevation for effective management.