Head trauma can cause anisocoria (unequal pupils).

Head trauma can cause anisocoria (unequal pupils).

• A. Head trauma can cause anisocoria (unequal pupils)
• B. Head trauma has no effect on pupils
• C. Pupils always reflect lighting not injury
• D. Pupils always equal in trauma

Answer: (A)

Pupil size and reaction to light are controlled by the brain’s nerves that manage the iris, so head trauma can disrupt those pathways and produce anisocoria. When injury affects the oculomotor nerve or increases intracranial pressure, one pupil may become larger and less reactive than the other. This makes the statement true: head trauma can cause unequal pupils, and such a finding is a important neurological sign that may indicate a serious injury. The other ideas— that trauma has no effect on pupils, that pupils reflect lighting regardless of injury, or that pupils are always equal after trauma—don’t fit because trauma can alter either the size or the light reflex of a pupil, or both.

Pupil size and reaction to light are controlled by the brain’s nerves that manage the iris, so head trauma can disrupt those pathways and produce anisocoria. When injury affects the oculomotor nerve or increases intracranial pressure, one pupil may become larger and less reactive than the other. This makes the statement true: head trauma can cause unequal pupils, and such a finding is a important neurological sign that may indicate a serious injury. The other ideas— that trauma has no effect on pupils, that pupils reflect lighting regardless of injury, or that pupils are always equal after trauma—don’t fit because trauma can alter either the size or the light reflex of a pupil, or both.