Idiopathic intracranial hypertension

Idiopathic intracranial hypertension (IIH), previously known as pseudotumor cerebri and benign intracranial hypertension, is a condition characterized by increased intracranial pressure (pressure around the brain) without a detectable cause. The main symptoms are headache, vision problems, ringing in the ears, and shoulder pain. Complications may include vision loss. This condition is idiopathic, meaning there is no known cause. Risk factors include being overweight or a recent increase in weight. Tetracycline may also trigger the condition. The diagnosis is based on symptoms and a high opening pressure found during a lumbar puncture with no specific cause found on a brain scan. Treatment includes a healthy diet, salt restriction, and exercise. The medication acetazolamide may also be used along with the above measures. A small percentage of people may require surgery to relieve the pressure. About 2 per 100,000 people are newly affected per year. The condition most commonly affects women aged 20–50. Women are affected about 20 times more often than men. The condition was first described in 1897. The most common symptom of IIH is severe headache, which occurs in almost all (92–94%) cases. It is characteristically worse in the morning, generalized in character and throbbing in nature. It may be associated with nausea and vomiting. The headache can be made worse by any activity that further increases the intracranial pressure, such as coughing and sneezing. The pain may also be experienced in the neck and shoulders. Many have pulsatile tinnitus, a whooshing sensation in one or both ears (64–87%); this sound is synchronous with the pulse. Various other symptoms, such as numbness of the extremities, generalized weakness, pain and/or numbness in one or both sides of the face, loss of smell, and loss of coordination, are reported more rarely; none are specific for IIH. In children, numerous nonspecific signs and symptoms may be present. The increased pressure leads to compression and traction of the cranial nerves, a group of nerves that arise from the brain stem and supply the face and neck.