What is Idiopathic Intracranial Hypertension (IIH)?

From the Guidelines

Idiopathic intracranial hypertension (IIH) should be managed with a multidisciplinary approach, prioritizing weight loss, acetazolamide as the first-line medication, and regular ophthalmological follow-up to prevent permanent vision loss. The condition is characterized by increased pressure around the brain without an identifiable cause, and its symptoms include headaches, vision changes, and pulsatile tinnitus 1.

Key Principles of Management

• Weight loss is essential for overweight patients, as even modest weight reduction can significantly improve symptoms 1
• Acetazolamide (Diamox) is the first-line medication, usually starting at 500mg twice daily and potentially increasing to 1000-2000mg daily if needed 1
• Topiramate (25-100mg twice daily) is an alternative that also helps with migraine symptoms and weight loss 1
• Regular follow-up with ophthalmology is essential to monitor vision, as untreated IIH can lead to permanent vision loss 1
• Patients should also be advised to avoid medications that may worsen IIH, such as tetracyclines, vitamin A derivatives, and certain hormonal treatments 1

Surgical Interventions

For severe cases or those not responding to medication, surgical interventions like optic nerve sheath fenestration or cerebrospinal fluid shunting procedures may be necessary 1. The management of IIH should be guided by three main principles: (1) to treat the underlying disease; (2) to protect the vision; and (3) to minimise the headache morbidity 1.

Importance of Interdisciplinary Expertise

The condition occurs due to impaired cerebrospinal fluid absorption, leading to increased intracranial pressure that can damage the optic nerve and cause symptoms like headaches, vision changes, and pulsatile tinnitus 1. An interdisciplinary approach, including neurology, neurosurgery, neuroradiology, ophthalmology, nursing, primary care doctors, and patient representatives, is crucial for optimal management of IIH 1.

From the Research

Idiopathic Intracranial Hypertension (IIH) Overview

• IIH is a syndrome of unknown cause that is increasing in frequency, typically affecting women of childbearing age and obese individuals 2.
• Patients with IIH often present with headaches and visual changes that may become chronic 2.

Diagnosis of IIH

• The diagnosis of IIH involves excluding secondary causes of increased intracranial pressure 3.
• Imaging plays a crucial role in the diagnosis of IIH, with subtle findings such as a partially empty sella, flattening of the posterior globe, cupping of optic disks, and distension of the optic nerve sheaths 2.
• Intracranial venography is also important in the diagnosis of IIH, as many patients have dural venous sinus stenoses 2.

Treatment of IIH

• Treatment of IIH varies from institution to institution and may involve medical and surgical interventions 2.
• Osmotherapy, including the use of mannitol and hypertonic saline, is considered the mainstay of medical therapy for increased intracranial pressure 4.
• Studies have compared the effectiveness of hypertonic saline and mannitol in treating elevated intracranial pressure, with some suggesting that hypertonic saline may be more effective in certain cases 5, 6.

Management of Elevated Intracranial Pressure

• The goal of treatment for elevated intracranial pressure is to maintain or re-establish adequate cerebral blood flow and prevent herniation 4.
• Hyperosmolar therapy, including the use of hypertonic saline and mannitol, is used to decrease intracranial pressure 4, 5, 6.
• The choice of hyperosmolar agent may depend on the individual patient's needs and the specific clinical scenario 5, 6.