Increased pressure within the skull is a symptom of idiopathic intracranial hypertension (intracranial pressure). It is unknown what causes the condition. People experience headaches on a regular or near-daily basis, along with nausea, blurred or double vision, and noises inside the head (tinnitus).
A spinal tap is performed after imaging of the head is performed to rule out possible reasons for elevated pressure.
Vision loss can occur if treatment is not received quickly.
Weight loss, diuretics to lower brain fluids, and spinal taps did regularly to relieve pressure can all assist, although surgery is sometimes required.
Idiopathic intracranial hypertension affects roughly one out of every 100,000 persons, with the majority of cases occurring in women during their reproductive years. It is, however, 20 times more common among young overweight women. As more people get overweight, the disorder is becoming more widespread.
Idiopathic Intracranial Hypertension: What Causes It?
It’s unclear what causes the pressure inside the skull to rise. However, because the major veins (venous sinuses) that assist drain blood from the brain in certain persons are smaller than in most people, they are more prone to idiopathic intracranial hypertension. Blood drains from the brain more slowly in these persons, producing a blood back-up and increasing pressure in the brain and/or within the skull.
It’s unclear exactly how being overweight adds to increased pressure inside the skull. Excess abdominal fat, on the other hand, might raise chest pressure, preventing blood from flowing normally from the head to the chest. As a result, the pressure inside the skull may rise.
The increased pressure in idiopathic intracranial hypertension is not caused by other conditions such as tumors, infections, blood clots, or obstructions that prevent the fluid that surrounds the brain (cerebrospinal fluid) from draining correctly.
The onset of idiopathic intracranial hypertension in most persons cannot be linked to a specific incident. When corticosteroids are withdrawn or growth hormone is administered, this disease can occur in youngsters. People who use tetracycline antibiotics or significant levels of vitamin A may acquire the disease.
Idiopathic Intracranial Hypertension Symptoms
Idiopathic intracranial hypertension is generally characterized by a daily headache that affects both sides of the head. The headache may be minor at first, but it might vary in strength and become severe. Nausea, double or blurred vision, and noises inside the head that occur with each pulse beat are all possible symptoms of a headache (called pulsatile tinnitus). A few persons experience no symptoms at all.
The optic nerve may expand around the eyeball as a result of increased pressure within the skull, a disease known as papilledema. Using an ophthalmoscope, doctors can examine the swelling at the back of the eye.
The loss of peripheral (side) vision is the first indicator of vision issues. This loss may go unnoticed at first. As a result, humans may unintentionally collide with items. Vision may be obscured for a short period, sometimes as a result of shifting positions, and the blurring may come and go. Vision becomes blurry later in the condition, and people may go blind quickly. One-third of people lose eyesight in one or both eyes, either partially or totally. Even if the pressure around the brain is alleviated, eyesight normally does not return once it has been lost.
In some patients, the condition becomes chronic and worsens with time, putting them in danger of blindness. To prevent visual loss, doctors closely monitor and treat such persons.
In roughly 10% to 20% of persons, idiopathic intracranial hypertension recurs.
Idiopathic Intracranial Hypertension Diagnosis
Based on symptoms and the results of a physical examination, doctors suspect idiopathic intracranial hypertension. When a doctor notices papilledema during a regular ophthalmoscope examination, they may suspect it.
Doctors check the field of vision (the total region of vision viewed out of each eye), including peripheral vision, if they suspect idiopathic intracranial hypertension. If they haven’t already done so, they use an ophthalmoscope to inspect the inside of the eye.
The big veins (called venous sinuses) that convey blood from the brain are evaluated using magnetic resonance venography. Doctors might perform this test to see if the venous sinuses are constricted or clogged. In persons with idiopathic intracranial hypertension, narrowed venous sinuses may be the only abnormality detected by imaging testing. Other anomalies that could increase pressure within the skull are also checked using magnetic resonance imaging (MRI) of the brain.
The pressure of the cerebrospinal fluid is measured and the fluid is analyzed via a spinal tap (lumbar puncture). The fluid pressure in the brain is elevated in idiopathic intracranial hypertension, often to dangerously high levels. The fluid’s composition is normally normal. The pressure inside the head reduces, the venous sinuses may open, and more blood may flow from the brain when spinal fluid is withdrawn during the spinal tap. As a result, the headache becomes less severe.
These tests can lead to finding possible causes of elevated cranial pressure such as a brain tumor blocking the venous sinuses.
Idiopathic Intracranial Hypertension Treatment
- Topiramate or acetazolamide to reduce intracranial pressure
- Pain painkillers or a migraine-treating medication
- Weight loss, if necessary
- Surgery to relieve pressure within the skull is sometimes necessary.
- Idiopathic intracranial hypertension can sometimes go away on its own.
Idiopathic intracranial hypertension is treated by focusing on the following:
- Lowering the pressure inside the skull
- Vision preservation
Aspirin, acetaminophen, or migraine medications (particularly topiramate—see table Some Migraine Medications) may help relieve the pain. Topiramate can also aid in weight loss and the reduction of intracranial pressure.
Tetracycline and other drugs that have been linked to the disease should be avoided.
Reduced pressure inside the skull
People with idiopathic intracranial hypertension who are overweight should lose weight in order to lessen pressure within the skull. Idiopathic intracranial hypertension can be relieved by losing as little as 10% of one’s body weight. Weight loss programs are frequently ineffective.
To help relieve pressure within the skull, doctors frequently prescribe acetazolamide or topiramate, both of which are taken by mouth. Because they limit the amount of cerebrospinal fluid produced in the brain, acetazolamide and topiramate are effective.
The value of performing daily or weekly spinal taps to drain cerebrospinal fluid is debatable. When people are at risk of losing their vision while waiting for more effective treatment, this procedure may be used (such as surgery to relieve the pressure within the skull). People are regularly watched if they have regular spinal taps to see if their pressure is lowering. To see if the spinal taps enlarged the venous sinuses, a CT venography or magnetic resonance venography may be performed again. More blood can flow out of the brain when these veins widen, and pressure within the skull is lowered.
In persons with idiopathic intracranial hypertension, the greatest concern is permanent visual loss. Because peripheral vision loss occurs early, before people realize it, an ophthalmologist uses an automated instrument to evaluate vision, including peripheral vision, on a regular basis (a test called perimetry). The device generates a visual stimulus (such as a flash of light) and records the individual’s responses. The results are really accurate. This regular examination allows doctors to detect eye abnormalities as soon as feasible.
If vision continues to decline despite these efforts, surgery to relieve pressure within the skull may be required, and vision may be saved. Procedures include the following:
Optic Nerve Sheath
Slits are cut in the covering of the optic nerve behind the eyeball during optic nerve sheath fenestration. These openings allow cerebrospinal fluid to escape and be absorbed in the tissues surrounding the eye.
A shunt is a plastic tube drain that is permanently installed. It can be surgically implanted to drain excess cerebrospinal fluid. The shunt is implanted either within the brain or in the lower back, right below the spinal cord. Excess fluid can be drained by running the tube under the skin, usually to the abdomen.
A wire mesh tube (stent) is inserted into the constricted venous sinus during stenting. After that, the stent is opened to enlarge the venous sinus.
Surgical weight loss
If alternative treatments for idiopathic intracranial hypertension have failed, surgery to help with weight loss (bariatric surgery, such as a gastric bypass) may be considered. It has the potential to cure the disease if it is successful.