Overview
Idiopathic intracranial hypertension (IIH) happens when pressure inside the skull rises without a clear cause. IIH also is called pseudotumor cerebri (SOO-doe-too-mur SER-uh-bry). The higher intracranial pressure can lead to headaches, vision changes and a whooshing sound in the ears. Healthcare professionals can confirm the diagnosis with eye exams and brain imaging. Treatment aims to lower the pressure, protect vision and ease symptoms.
Symptoms of IIH mimic those of a brain tumor. The increased intracranial pressure can cause swelling of the nerve fibers that connect the eye to the brain, known as the optic nerve. The swelling can result in vision loss. Medicines often can reduce this pressure and symptoms such as headaches. Sometimes, surgery is necessary.
IIH can occur in children and adults, but it's most common in women of childbearing age with obesity.
Symptoms
Idiopathic intracranial hypertension (IIH), also called pseudotumor cerebri, symptoms might include:
- Bad headaches that might begin behind the eyes.
- A whooshing sound in your head that pulses with your heartbeat.
- Nausea, vomiting or dizziness.
- Vision loss.
- Brief episodes of blindness, lasting a few seconds and affecting one or both eyes.
- Trouble seeing to the side.
- Double vision.
- Seeing light flashes.
- Neck, shoulder or back pain.
Sometimes symptoms that have resolved can return months or years later.
Causes
The cause of idiopathic intracranial hypertension is not known. If a cause is found, the condition is called secondary intracranial hypertension, rather than idiopathic.
The brain and spinal cord are surrounded by cerebrospinal fluid. The fluid cushions these vital tissues and protects them from injury. Cerebrospinal fluid is produced in the brain. It is eventually absorbed into the bloodstream at a rate that usually allows the pressure in the brain to remain constant.
When cerebrospinal fluid isn't absorbed into the bloodstream at the proper rate, pressure inside the skull increases.
Risk factors
Obesity, medicines and health conditions have been associated with idiopathic intracranial hypertension.
Obesity
Women who are obese and of childbearing age are more likely to develop idiopathic intracranial hypertension.
Medicines
Substances linked to secondary intracranial hypertension include:
- Growth hormone.
- A class of antibiotics called tetracyclines, particularly doxycycline and minocycline.
- A class of medicines called vitamin A derivatives, particularly isotretinoin.
Health problems
Conditions and diseases that have been linked to secondary intracranial hypertension include:
- Addison's disease.
- Anemia.
- Blood-clotting disorders.
- Kidney disease.
- Lupus.
- Polycystic ovary syndrome.
- Sleep apnea.
- Underactive parathyroid glands.
Complications
For some people with idiopathic intracranial hypertension, their vision continues to worsen, leading to visual loss.
