Pseudotumor cerebri is a condition in which high cerebrospinal fluid pressure inside your head can cause problems with vision and headache.
The term "pseudotumor" (false tumor), comes from the days before imaging studies, when doctors who noted swelling of the optic disc considered the possibility of a brain tumor. Patients with optic disc swelling but no evidence of a tumor were said to have "pseudotumor".
In pseudotumor cerebri, the spinal fluid is blocked from flowing back out of the head as it should, leading to high pressure within the cerebrospinal fluid inside the head. This pressure results in swelling of the optic disc at the back of the eye, which can damage the optic nerve and cause vision loss. High pressure may also cause damage to the nerves that move the eyes, resulting in double vision.
The reason for decreased outflow of spinal fluid is not clear. Because this dondition seems to occur more often in overweight young women, a hormonal influence is suspected.Pseudotumor may also occur in children, men and patients who are not overweight. In some cases, antibiotic and steroid use may be associated with pseudotumor, as well as high doses of vitamin A.
The most common symptoms of high spinal fluid pressure inside the head are headache and visual loss. The headache may be located anywhere but is frequently in the back of the neck. This pain may awaken the patient in the middle of the night and may worsen with bending or stooping.
Other symptoms include:
- dimming, blurring or graying of vision
- difficulty seeing to the side
- brief visual disturbances
- double vision
- rushing noise in the ears
- nausea and vomiting
An ophthalmologist will carefully measure vision, check the light reaction of the pupils, examine the back of the eye and may evaluate the visual field. Because other conditions may produce similar symptoms to pseudotumor cerebri, an MRI scan is necessary for accurate diagnosis. A spinal tap is also necessary to check for elevated cerebrospinal fluid and to make sure there are no other cerebrospinal fluid abnormalities.
If there are no significant headaches or evidence of vision loss, no treatment may be necessary. If the patient experiences any problems, however, certain medications used in treating glaucoma can lower the cerebrospinal fluid pressure in the head by reducing its production. Diuretics may also be prescribed. One of the most effective treatments is weight reduction in overweight patients. Pressure may also be lowered by draining off spinal fluid through repeated spinal taps.
Repeated visual field testing is essential in following patients with pseudotumor cerebri. If the visual field is worsening or there is a decrease in central acuity of vision and there are no severe headaches, a small hole or multiple slits may be placed in the optic nerve sheath (optic nerve sheath fenestration). This is done to protect the optic nerve from further damage. If severe headaches accompany the visual loss, a shunting procedure may be required.