Idiopathic Intracranial Hypertension (IIH)

Overview


Plain-Language Overview

Idiopathic Intracranial Hypertension (IIH) is a condition where the pressure inside the skull is higher than normal without an obvious cause like a tumor or infection. It affects the brain and nervous system, specifically the fluid that surrounds the brain called cerebrospinal fluid (CSF). This increased pressure can cause symptoms such as headaches, vision problems, and ringing in the ears. The condition mainly affects young, overweight women but can occur in others as well. If untreated, it can lead to permanent vision loss due to pressure on the optic nerves. Diagnosis often involves imaging and measuring the pressure of the CSF. Treatment focuses on reducing this pressure to protect brain function and eyesight.

Clinical Definition

Idiopathic Intracranial Hypertension (IIH) is characterized by elevated intracranial pressure without an identifiable cause such as mass lesions, hydrocephalus, or infection. The core pathology involves increased cerebrospinal fluid pressure leading to papilledema and symptoms of raised intracranial pressure. The exact mechanism is unclear but is thought to involve impaired CSF absorption or increased CSF production. It predominantly affects obese women of childbearing age. Clinically, it presents with headache, transient visual obscurations, pulsatile tinnitus, and diplopia due to sixth nerve palsy. The major clinical significance lies in the risk of permanent vision loss if untreated. Diagnosis requires exclusion of secondary causes and confirmation of elevated CSF pressure on lumbar puncture.

Clinical Presentation


Diagnostic Workup


Pathophysiology


Treatments


Prevention


Outcome & Complications


Differential Diagnoses


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