What is Idiopathic Intracranial Hypertension?
Idiopathic intracranial hypertension (IIH) is a condition where pressure inside your head rises, causing vision problems, headaches and other symptoms. This happens when fluid from the brain (called cerebrospinal fluid, or CSF) does not flow out of the head as it should.
When pressure around the brain is too high it can put pressure on the optic nerve causing it to swell. This may eventually damage the optic nerve, often causing vision loss. High pressure can also damage the nerves that move the eyes, causing double vision.
What Causes Idiopathic Intracranial Hypertension?
Doctors do not know for sure what causes IIH. However, they suspect hormones play a role since this condition is more common in young, overweight women.
Sometimes children and adults who are not overweight have IIH. These cases may be related to infection, or to using antibiotics, steroids or high doses of vitamin A.
What Are the Symptoms of Idiopathic Intracranial Hypertension?
- Headaches, often at the back of your neck. These headaches may be so severe that they wake you up at night. Your headaches may be worse when you stoop or bend down.
- Vision changes. Your vision may seem dim, blurry, or dull. There may be short periods of time where your vision completely disappears. You might have trouble with peripheral (side) vision. You also may have double vision or other vision problems when you stoop down or bend over.
- Hearing problems, such as a rushing, swishing or ringing sound in your ear.
- Nausea and vomiting.
How Is Idiopathic Intracranial Hypertension Diagnosed?
Your ophthalmologist will do a series of tests to diagnose idiopathic intracranial hypertension (IIH). They may include:
- An eye exam. Your ophthalmologist will check your optic nerve for swelling. He or she will also test to see if you have any blank spots in your field of vision.
- An MRI or CT scan. These scans help to check whether your symptoms are due to IIH or caused by other medical problems.
- A spinal tap. This is when your doctor measures the pressure of your spinal fluid. He or she will also draw fluid to test it for any problems.
How Is Idiopathic Intracranial Hypertension Treated?
You might not need any treatment if IIH is not causing severe headaches or vision loss. If you do need treatment, here are some options:
- Your doctor may prescribe medicine that treats glaucoma to help lower your CSF pressure. You might also be prescribed diuretics—medicine that helps your body get rid of excess fluid.
- If you are overweight or obese, your doctor may want you to lose weight.
- To protect your optic nerve from further damage, your ophthalmologist may make a tiny hole or several tiny slits in part of the optic nerve. This helps relieve some of the pressure on the nerve.
- If your symptoms are severe, your ophthalmologist may want you to have a shunt placed in your head. This is a tiny tube that carries fluid away from where it builds up. Then the fluid can be absorbed elsewhere in the body. This procedure lowers the pressure in your head.