What Is It?
Pseudotumor cerebri is a condition with characterized by an increase in pressure within the skull (called the intracranial pressure), where the brain sits, with no clear cause. It is called pseudo
-tumor because it presents similar to some brain tumors with an increase in pressure which causes symptoms such as headache, nausea and vomiting and blurred vision. Before the invention of the CT and MRI scan which allows doctors to "see" inside the head, this condition sometimes fooled doctors into thinking the patient had a brain tumor. However, no tumor is present, hence the "pseudo".
Pseudotumor cerebri is not due to a tumor and therefore is usually classified with hydrocephalus and related conditions. Hydrocephalus also results in increased pressure in the head and can have similar symptoms but is usually caused by a disruption of the normal flow and dynamics of the fluid in and around the brain, the cerebrospinal fluid. This causes the ventricles, the fluid-filled spaces within the brain, to enlarge in most forms of hydrocephalus. This does not typically occur in pseudotumor.
The underlying cause of pseudotumor cerebri in most patients is not known. It may be related to an increase in cerebrospinal fluid, similar to hydrocephlus. It is a relatively rare disease but there are some risk factors which appear to increase one's risk of developing the condition. In particular, young, obese women are at the highest risk. Some medications, such as lithium, oral contraceptives, tetracycline, steroids and excess vitamin A, have been loosely associated with it. Likewise, other health problems may be linked to the disease, including head injury, kidney disease, lupus, lyme disease, mononucleosis and hypoparathyroidism. However, all of these are simply associated with pseudotumor cerebri and are not, in and of themselves, causes of the disease.
What Types of Symptoms Are Typical?
The most common symptoms of pseudotumor are headache. The headache can be moderate to severe and are often frontal or in the area behind the eyes. The headaches can wake the individual from sleep and may be worse with eye movement.
Other common symptoms include ringing in the ears that pulses with each heartbeat, nausea, vomiting, blurred vision, loss of peripheral vision and double vision. The severity of symptoms can vary quite a bit between patients. For example, a small percentage of patients will develop severe loss of vision or even blindness.
While the symptoms usually occur in an attack that lasts a while and then resolves, some patients may have recurrences months or years later.
How Is The Diagnosis Typically Made?
Clinically, doctors will look for signs or symptoms consistent with pseudotumor cerebri. However, because similar symptoms can be caused by other diseases, such as a brain tumor or hydrocephalus, other testing is also done.
An eye exam will usually show papilledema, a swelling of the nerve in the eye which is caused by an increase in pressure in the skull. However, again, papilledema can be caused by other things as well.
Other tests which may be performed to confirm the diagnosis include CT or MRI scans of the brain. These can help rule out other conditions, such as a brain tumor or hydrocephalus. A spinal tap (lumbar puncture) or intracranial pressure monitoring may be done to look for evidence of increased pressure in the head which would be consistent with pseudotumor.
What Are Some Common Treatments?
Medications are usually first used to treat this condition. However, in more severe cases, particularly those with worsening vision, or cases which are resistant to treatment by medications alone, surgical options may be considered.
Medical options include a medication called acetazolamide (Diamox) which decreases the production of cerebrospinal fluid and may decrease the pressure in the skull in some patients. It is sometimes combined with other diuretic medications, particularly furosemide, which help the body to get rid of fluid by increasing the production of urine. Medications, such as migraine medications, may also be recommended to help treat the headaches associated with pseudotumor.
The surgical options considered in some patients with pseudotumor generally attempt to decrease the amount of pressure within the head and on the optic nerves, to both decrease symptoms and to protect the eyesight. An optic nerve sheath fenestration cuts a small hole into the membrane surrounding the nerve to the eye. This allows some fluid to escape and may decrease the pressure on the nerves. Another option is a shunt which diverts cerebrospinal fluid away from the head, decreasing pressure. Finally, some physicians find that a craniectomy, removing part of the skull, helps to allow the brain to expand and to decrease pressure.
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This site is not intended to offer medical advice. Every patient is different, and only your personal physician can help to counsel you about what is best for your situation. What we offer is general reference information about various disorders and treatments for your education.