What is Pseudotumor Cerebri?
Pseudotumor cerebri is a condition where there is increase in the intracranial pressure without any obvious cause. Intracranial pressure is the pressure inside the skull. The symptoms of pseudotumor cerebri mimic that of a brain tumor; however, pseudotumor cerebri has no tumor present. This condition can potentially result in loss of vision if not treated. Pseudotumor cerebri is commonly seen in overweight females who are of childbearing age; however, both adults and children can also suffer from this condition.
If the cause of increased intracranial pressure is not found, then the pseudotumor cerebri can also be referred to as idiopathic intracranial hypertension. Due to the increased intracranial pressure occurring in the pseudotumor cerebri, there is swelling of the optic nerve which can result in loss of vision. Medications help in decreasing this pressure, however, in some cases, surgery may be required.
Causes of Pseudotumor Cerebri
The exact cause of why pseudotumor cerebri occurs is unknown in majority of the patients. However, excessive amount of cerebrospinal fluid present inside the bony confines of the skull can lead to this condition. Cerebrospinal fluid surrounds the brain and spinal cord and acts as a shock absorber and protects the brain and spinal cord from injury. The brain produces the cerebrospinal fluid. The bloodstream eventually absorbs this cerebrospinal fluid. Any problem in this absorption process can result in elevated intracranial pressure which is seen in pseudotumor cerebri.
Generally, when the contents of the skull exceed their capacity, then it leads to increase of the intracranial pressure. For example, when a person has brain tumor, then the tumor increases the intracranial pressure as there is no more room to accommodate the tumor. Similarly, there is increase in the intracranial pressure or swelling of the brain, when there is excessive cerebrospinal fluid.
According to research, many patients having pseudotumor cerebri also have stenosis or narrowing of transverse sinuses in the brain. Studies are still going on to find out if this is the cause or effect of the condition.
Risk Factors of Pseudotumor Cerebri
- Obesity increases the risk of developing Pseudotumor Cerebri, especially in women. Obese women below the age of 44 are at an increased risk for developing Pseudotumor Cerebri.
- Medications, such as tetracycline, growth hormone and excess of vitamin A, have shown to increase the risk of pseudotumor cerebri.
- Some diseases and medical conditions are linked to pseudotumor cerebri and these include anemia, Addison's disease, blood-clotting disorders, Behcet's syndrome, lupus, sleep apnea, polycystic ovary syndrome, uremia and underactive parathyroid glands.
Signs & Symptoms of Pseudotumor Cerebri
In Pseudotumor Cerebri, patient experiences symptoms similar to brain tumor which include:
- Patient suffering from Pseudotumor Cerebri may experience symptoms of moderate to severe headaches which start behind the eyes. Movement of the eyes worsens the headache.
- Patient has nausea and vomiting.
- Pseudotumor Cerebri Patients can have symptoms of dizziness.
- Patient experiences pulsatile tinnitus, which is ringing in the ears that pulses according to the heartbeat.
- Vision becomes dimmed or blurry.
- There is difficulty in seeing to the side.
- Pseudotumor Cerebri patients may also have symptoms of small episodes of blindness, which last only a few seconds involving either one or both the eyes.
- Diplopia or double vision can occur.
- Patient experiences photopsia, which is seeing flashes of light.
- There is pain in the neck, back or shoulder.
Diagnosis of Pseudotumor Cerebri
- Medical history and physical examination of the patient is conducted.
- Eye exams are conducted by an ophthalmologist. If pseudotumor cerebri is suspected, then the patient will have papilledema in the posterior region of the eye, which is a distinctive type of swelling of the optic nerve.
- Visual fields tests are also done to check for any blind spots in the vision of both the eyes.
- Brain imaging tests are done, which include CT scan or MRI scan, to exclude other conditions which cause similar symptoms, such as blood clots and brain tumors.
- Lumbar puncture or spinal tap is a test done to measure the pressure within the skull, along with the protein and glucose levels. A needle is inserted between two lower back vertebrae and a small amount of cerebrospinal fluid is extracted and sent to laboratory for testing.
Treatment for Pseudotumor Cerebri
The aim of treatment for pseudotumor cerebri is to alleviate the symptoms and prevent worsening of the eyesight.
Medications to Treat Pseudotumor Cerebri
Medications are prescribed to control the symptoms. The following medications are prescribed for pseudotumor cerebri:
- Glaucoma medicines such as acetazolamide help in decreasing the production of cerebrospinal fluid. This medicine also helps in improving symptoms. Side effects may include fatigue, stomach upset, kidney stones, tingling of mouth, fingers and toes.
- If acetazolamide is not effective, then Diuretics such as furosemide are prescribed in combination. Diuretic increases urine output which results in decrease of fluid retention.
- Migraine medications can also help in relieving severe headaches which occur due to pseudotumor cerebri.
Surgery for Pseudotumor Cerebri
Surgery is needed if there is worsening of the vision to decrease the intracranial pressure or to reduce the pressure around the optic nerve. Patient should get regular vision checkups once he/she has had pseudotumor cerebri.
- Optic nerve sheath fenestration is a procedure where the surgeon cuts a window into the membrane, which covers the optic nerve, thus allowing the excess cerebrospinal fluid to flow out. With this procedure, there is improvement or stabilization of the vision in most cases. Many patients who get this procedure done on one eye notice an improvement in the vision for both eyes. There are some cases, however, where this surgery may not be successful and can even exacerbate vision problems.
- Spinal fluid shunt is another type of surgery where a shunt, which is a long, thin tube is inserted in the brain or the lower spine. This shunt helps in draining away the excess cerebrospinal fluid. The tube is placed beneath the skin up to the abdomen, where the excess fluid is discharged by the shunt. There is improvement in the symptoms of some patients who have this procedure. The shunts, however, can become blocked and commonly may need additional surgeries for them to be functioning properly. Complications of this procedure include infections and low-pressure headaches. Spinal fluid shunt is considered only if other treatment options have not relieved the pseudotumor cerebri.
Lifestyle Modifications for Pseudotumor Cerebri
Weight loss is recommended if the patient is obese. Obesity greatly increases of a young woman to develop pseudotumor cerebri. Women who have gained a moderate amount of weight are also at an increased risk for developing this condition. It is important to lose the excess weight and arrive and maintain a healthy weight to decrease the chances of developing this condition. Losing excess weight helps in improving the symptoms. A dietitian will help in setting up a diet plan for losing weight.