Pseudotumor cerebri Flashcards
Papilledema is an indication for . . .
. . . emergent head CT with contrast
Who tends to be affected by pseudotumor cerebri?
Obese women between ages 20-40
Papilledema on exam
Hydrocephalus
Abnormal excessive accumulation of CSF in the brain
Pathophysiology of papilledema
Results from axoplasmic flow stasis
Increased intracranial pressure is transmitted to the subarachnoid space, and in turn to the optic nerve and sheath. As pressure increases, the sheath is compressed around the axon, preventing normal axoplasmic transport.
The result is accumulation of axonal transport components resulting in edema of the nerve and the optic disc.
When might a clinician perform a high volume tap?
When the opening pressure is greather than 20 mL water
High volume tap is removal of ~30-40 mL of CSF
The longer papilledema goes on. . .
. . . the more nerves are damaged
Papilledema can cause irreversible damage to nerve axons and loss of peripheral vision.
All patients with significant papilledema require ophthalmologic examination for visual fields.
Diagnostic criteria for pseudotumor cerebri
- Findings of increased intracranial pressure (papilledema)
- Nonfocal neurologic signs (exception of 6th nerve palsy)
- Normal imaging studies (exception slit-like ventricles)
- Normal CSF studies (exception increased opening pressure)
Venous return theory of pseudotumor cerebri
Obesity leads to increased intra-abdominal pressure
This raises cardiac filling pressures
This leads to impaired venous return from the brain
Classic features of pseudotumor cerebri
- Headache (diffuse, worse in the morning, worsens with Valsalva)
- Transient visual obscuration exacerbated by bending over or standing up quickly
- N/V
- Pulsatile tinnitus
- 6th nerve palsy
Discontinuation of ___ has been associated with the development of pseudotumor cerebri
Discontinuation of corticosteroids has been associated with the development of pseudotumor cerebri
Treatment of pseudotumor cerebri
- Acute:
- Large-volume LP
- Chronic:
- Weight management (essential to control of disease, bariatric surgery should be considered)
- Carbonic anhydrase inhibitors (acetazolomide, topiramate)
- Furosemide (alone or in combination with above)
- Medically refractory:
- VP shunt
- LP shunt
- Rapid or progressive vision loss:
- Optic nerve sheath fenestration
Papilledema in the presence of normal opening pressure suggests. . .
. . . optic nerve trauma
Medications that may induce pseudotumor cerebri
- vitamin A analogs
- Tetracyclines