Pseudotumor cerebri (SOO-doe-too-mur SER-uh-bry) occurs when the pressure inside your skull (intracranial pressure) increases for no obvious reason.
Symptoms mimic those of a brain tumor, but no tumor is present. Pseudotumor cerebri can occur in children and adults, but it's most common in women of childbearing age who are obese.
When no underlying cause for the increased intracranial pressure can be discovered, pseudotumor cerebri may also be called idiopathic intracranial hypertension.
The increased intracranial pressure associated with pseudotumor cerebri can cause swelling of the optic nerve and result in vision loss. Medications often can reduce this pressure, but in some cases, surgery is necessary.
Pseudotumor cerebri signs and symptoms may include:
- Moderate to severe headaches that may originate behind your eyes and worsen with eye movement
- Ringing in the ears that pulses in time with your heartbeat (pulsatile tinnitus)
- Nausea, vomiting or dizziness
- Blurred or dimmed vision
- Brief episodes of blindness, lasting only a few seconds and affecting one or both eyes (visual obscurations)
- Difficulty seeing to the side
- Double vision (diplopia)
- Seeing light flashes (photopsia)
- Neck, shoulder or back pain
The exact cause of pseudotumor cerebri in most individuals is unknown, but it may be linked to an excess amount of cerebrospinal fluid within the bony confines of your skull.
Your brain and spinal cord are surrounded by cerebrospinal fluid, which acts like a cushion to protect these vital tissues from injury. This fluid is produced in the brain and eventually is absorbed into the bloodstream. The increased intracranial pressure of pseudotumor cerebri may be a result of a problem in this absorption process.
In general, your intracranial pressure increases when the contents of your skull exceed its capacity. For example, a brain tumor generally increases your intracranial pressure because there's no room for the tumor. The same thing happens if your brain swells or if you have too much cerebrospinal fluid.
Several studies indicate that many people with pseudotumor cerebri have a narrowing (stenosis) in two large sinuses in the brain (transverse sinuses). Studies are determining whether this is an effect or a cause of the condition.
The following factors have been associated with pseudotumor cerebri:
Obesity has been associated with pseudotumor cerebri, which occurs in 1 to 2 people in 100,000. In women who are obese, about 4 to 21 in 100,000 develop the condition. Women under the age of 44 who are obese are more likely to develop the disorder.
Substances that have been linked to pseudotumor cerebri include:
- Growth hormone
- Excess vitamin A
Other medications may be associated with pseudotumor cerebri, but further research is needed.
The following conditions and diseases have been linked to pseudotumor cerebri:
- Addison's disease
- Behcet's syndrome
- Blood-clotting disorders
- Kidney disease
- Polycystic ovary syndrome
- Sleep apnea
- Underactive parathyroid glands
Some people with pseudotumor cerebri experience progressively worsening vision and may eventually become blind.
Even if your symptoms have resolved, they can recur months or even years later.