Question

Which of these is NOT useful in arriving at a diagnosis of moderate papilledema in a patient of head injury?

• A. Impaired pupillary reflex
• B. Hyperemia
• C. Filling of the physiological cup
• D. Blurring of the margins

Hint:

Papilledema is a fundus finding, pupillary reflex usually stays normal until very late disease.

Answer 1

The Correct Option is A

Step 1: Recall what papilledema is.
Papilledema is swelling of the optic disc caused by raised intracranial pressure, which is transmitted along the optic nerve sheath and blocks normal axoplasmic flow at the disc, causing it to swell.

Step 2: Recall the early to moderate fundus signs.
On fundus exam, the earliest signs of papilledema include hyperemia (a flushed, engorged looking disc from dilated capillaries), filling of the physiological cup (the normal central depression becomes shallow and fills in as the disc swells), and blurring of the disc margins, first at the nasal edge and then all around. These are the standard signs doctors look for on ophthalmoscopy to grade papilledema from early to moderate to severe (chronic/atrophic) stages.

Step 3: Think about what pupillary reflex tells us.
The pupillary light reflex depends on the afferent visual pathway carrying light signals from the retina to the midbrain. In papilledema, especially moderate papilledema, vision and the pupillary reflex usually stay normal for a long time, because the swelling primarily affects the optic disc surface and retinal fibers without cutting off the reflex pathway early on.

Step 4: Contrast with optic neuritis.
An impaired pupillary reflex, specifically a relative afferent pupillary defect, is a hallmark of optic neuritis or optic nerve damage that directly disrupts the afferent pathway. Papilledema, until it becomes severe and chronic enough to cause optic atrophy, does not usually impair the pupillary reflex. So this sign does not help diagnose moderate papilledema.

Step 5: Confirm the other three are genuinely useful.
Hyperemia, filling of the cup, and blurring of the margins are all direct fundoscopic findings clinicians rely on to spot and grade papilledema.

Step 6: Final answer.
Impaired pupillary reflex is not a useful sign for diagnosing moderate papilledema.
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