Idiopathic Intracranial Hypertension - Causes, Complications, and Treatment

What Is Idiopathic Intracranial Hypertension?

Idiopathic intracranial hypertension is a neurological condition where one suffers increased pressure inside the head. The term idiopathic implies that the cause of raised pressure is unknown. The symptoms of idiopathic intracranial hypertension mimic that of a brain tumor. Hence, it is also known as pseudotumor cerebri. It mostly affects overweight or obese women who are of childbearing age. One may suffer permanent loss of eyesight and other complications if idiopathic intracranial hypertension is left untreated.

What Are the Possible Causes of Idiopathic Intracranial Hypertension?

The brain and spinal cord are suspended in a pool of clear fluid known as cerebrospinal fluid (CSF). The volume of cerebrospinal fluid is regulated by the body’s natural mechanism so that the pressure inside the head remains optimal. When this mechanism is impaired for some reason, the intracranial pressure rises beyond normal levels. The exact cause of this condition remains unknown, though experts have a few theories about the possibilities.

What Are the Risk Factors Leading To Idiopathic Intracranial Hypertension?

Though it is a rare neurologic condition, women of childbearing age are more at risk, especially those who are overweight or obese. Other risk factors are:

• Long-term use of certain drugs such as oral contraceptive pills, steroids, and certain antibiotics. Some may develop the condition after stopping these drugs as well.

• Pregnancy.

• Those who are suffering from kidney disease, sarcoidosis (abnormal inflammatory cell buildup inside organs and lymph nodes), or systemic lupus erythematosus (disease of the immune system affecting joints, skin, and organs).

What Are the Complications Arising From Idiopathic Intracranial Hypertension?

For some reason, there is too much cerebrospinal fluid getting collected inside the confined spaces inside one’s skull. The raised pressure puts tension on the brain and other structures in the head. Most importantly, it causes the swelling of the optic nerve (the nerve inside the brain that helps with eyesight). This condition is known as papilledema, and it results in temporary blindness. In the long run, one may suffer total damage to the optic nerve and end up becoming permanently blind.

What Are the Symptoms of Idiopathic Intracranial Hypertension?

Symptoms may vary from person to person, though three common symptoms affect the majority of affected individuals. They are:

1. Headache - It is the most prominent symptom. One suffers severe long-term headaches that keep coming every once in a while. The pain may be felt in different parts of the head each time, and the individual tends to stay nauseated and vomit a lot. There may be shoulder and neck pain as well.

2. Vision Changes - Problems with eyesight or temporary vision loss. The individual tends to go blind for a few seconds, or everything in front of the eyes goes dim and blurry. One may see two of every object and suffer pain while moving the eye sideways or bending over. As the disease progresses, one may suffer total blindness.

3. Tinnitus - One hears a typical rhythmic pulsating sound in the ears.

How Is Idiopathic Intracranial Hypertension Diagnosed?

The majority of affected individuals approach the doctor with complaints of headaches or eyesight issues. The doctor will want to know one’s medical background and lifestyle pattern. One needs to discuss all the symptoms with the doctor in detail, including how they started, the progression of symptoms, and the difficulties faced at present. This will be followed by specific tests for diagnosis, which are:

• A Detailed Eye Examination - An eye specialist will conduct a thorough eye examination for any signs of vision loss. One may have problems with clarity, seeing objects on the sides, identifying colors, or moving the eyes from side to side. An instrument called an ophthalmoscope is used to check the back of the eye where the optic nerve lies. This helps the doctor identify a typical feature called papilledema associated with idiopathic intracranial hypertension.

• Imaging Studies - The doctor may order imaging studies like computed tomography (CT) or magnetic resonance imaging (MRI) to evaluate the structural damage inside the brain. One needs to rule out other conditions that may elevate the intracranial pressure, such as brain tumors, hydrocephalus (inflammatory fluid collection inside the brain), etc.

• A Lumbar Puncture (Spinal Tapping) Procedure - Helps measure the pressure inside the head. In this procedure, the doctor inserts a needle into the lower back area of the spine right into the spinal column. This way, one can measure the pressure exerted by the cerebrospinal fluid or extract a sample of the fluid for laboratory tests.

What Is the Treatment for Idiopathic Intracranial Hypertension?

Treatment focuses on reducing excess intracranial pressure, preventing vision loss, and alleviating the symptoms. The following strategies are adopted:

1. If the individual does not have severe symptoms like vision loss, the doctor tries to manage the condition with medicines to lower the pressure inside the head. One may prescribe a group of drugs that belong to the category of carbonic anhydrase inhibitors, such as Acetazolamide. It helps in reducing cerebrospinal fluid production, thereby bringing down the excess volume of fluid. One may also prescribe a diuretic medication such as Furosemide for this purpose. For relieving the symptoms like headaches and others, painkillers and steroids are given. Medicines help reduce intracranial pressure in most individuals.

2. If the condition does not improve with tablets or if one suffers sudden vision loss, the doctor may go forward with surgical treatment. The surgery aims to reduce the pressure inside the skull and maintain it that way. One may perform the following:

• Shunting Procedure - This is the most common procedure where a rubber tube (catheter) is inserted into the fluid-filled part of the brain or spinal cord to drain the excess volume of CSF. A shunt has valves to regulate the amount of drainage corresponding to the fluid production so that the pressure inside the head is maintained at an optimum level. One may conduct a lumbar peritoneal shunt, where the tube is placed at the lower part of the spine and connected to the tummy for draining. Or a ventriculoperitoneal shunt, where the tube is inserted into the brain and connected all the way into the tummy by a tube for draining. One needs to have regular follow-ups to ensure proper working of the shunt, as it may get blocked, infected, or cause excess drainage occasionally.

• Optic Nerve Sheath Fenestration - Where the surgeon makes small cuts in the protective sheath around the optic nerve so that the excess CSF can escape through them. This helps relieve pressure from around the optic nerve and improves vision problems in the affected individual. However, the overall pressure within the skull does not reduce much in this procedure.

• Weight Reduction: Doctors recommend body weight reduction for individuals who are overweight or obese. This was found helpful in improving the symptoms to some extent.

Conclusion:

Optic nerve damage and subsequent loss of vision are the major complications of idiopathic intracranial hypertension. However, it can be managed effectively if one seeks medical help at the beginning stages of the condition. Some may need a combination of drugs as well as surgical treatment to control the symptoms. Idiopathic intracranial hypertension may recur in some individuals even years after the treatment. Hence one must undergo periodic reviews to look for eyesight problems and other symptoms.