Idiopathic Intracranial Hypertension: Symptoms and Management
Idiopathic intracranial hypertension (IIH) most commonly presents with progressively worsening headache, and management focuses on three core principles: treating the underlying disease (primarily obesity), protecting vision through pressure control, and minimizing headache-related disability. 1
Clinical Presentation and Symptoms
Primary Symptoms
Headache is the most frequent symptom in IIH, occurring in the majority of patients and representing a significant cause of quality-of-life impairment 1, 2, 3. The headache is typically progressively more severe and frequent, though the phenotype is highly variable and may mimic other primary headache disorders 1.
Associated Symptoms Suggesting Elevated Intracranial Pressure
- Transient visual obscurations: Unilateral or bilateral darkening of vision lasting typically seconds 1
- Pulsatile tinnitus: A whooshing sound synchronous with heartbeat 1, 2
- Visual blurring: Due to papilledema 1
- Horizontal diplopia: Typically from sixth cranial nerve palsy 1
- Back pain, neck pain (radicular), dizziness, and cognitive disturbances: Less specific but may occur 1
Important caveat: None of these symptoms are pathognomonic for IIH, but the combination of progressive headache with transient visual obscurations and pulsatile tinnitus should raise strong suspicion 1, 2.
Diagnostic Evaluation
Patient Demographics and Risk Factors
Typical IIH occurs in females of childbearing age with body mass index (BMI) greater than 30 kg/m² 1. The condition has a striking association with obesity, and the incidence is increasing parallel to the obesity epidemic 1, 4.
Atypical IIH (patients who are not female, not of childbearing age, or BMI below 30 kg/m²) requires more in-depth investigation to exclude secondary causes 1.
Essential Diagnostic Steps
Neurological examination should document:
- Cranial nerve function (typically only sixth nerve palsy should be present; other cranial nerve involvement suggests alternative diagnosis) 1
- Papilledema assessment by experienced clinician 1
Neuroimaging requirements:
- Urgent MRI brain within 24 hours (or CT if MRI unavailable, followed by MRI) 1
- CT or MR venography is mandatory within 24 hours to exclude cerebral sinus thrombosis 1
- Must show no hydrocephalus, mass, structural or vascular lesion, or abnormal meningeal enhancement 1
Lumbar puncture:
- Following normal imaging, all patients with papilledema require lumbar puncture to measure opening pressure and ensure CSF contents are normal 1
- Opening pressure interpretation varies, but elevated pressure confirms diagnosis when other criteria are met 1
Blood pressure measurement is mandatory to exclude malignant hypertension (diastolic blood pressure greater than specific thresholds) 1.
Management Approach
Three Core Treatment Principles
- Treat the underlying disease (primarily obesity)
- Protect vision through intracranial pressure control
- Minimize headache morbidity 1
Risk Stratification for Treatment Intensity
Fulminant IIH: Patients with precipitous decline in visual function within 4 weeks of diagnosis require urgent intervention 1.
Vision at imminent risk: Requires aggressive treatment escalation to surgical options 1.
Stable disease: Can be managed with medical therapy and close monitoring 1.
Medical Management
Acetazolamide remains the most commonly prescribed medication and is the best-supported drug treatment for IIH 1, 5, 3. However, there are no FDA-labeled therapies specifically for IIH 5.
Weight reduction is critical for disease modification:
- Bariatric surgery has proven effective in controlling elevated intracranial pressure 3
- Recent evidence suggests glucagon-like peptide-1 receptor agonists reduce intracranial pressure independent of weight reduction in phase II trials, representing a promising future treatment 5
Surgical Interventions
Indications for surgery:
- Imminent risk of visual loss despite medical therapy 1
- Fulminant IIH 1
- Progressive visual deterioration 1
Surgical options:
- CSF diversion procedures (ventriculoperitoneal or lumboperitoneal shunts): Best established option for pressure control 3
- Optic nerve sheath fenestration: May temporarily control pressure over the optic nerve and protect from visual deterioration 3
- Venous sinus stenting: Increasingly used and proven safe in selected cases with venous sinus stenosis 1, 5, 3
Important note: CSF diversion surgery and venous sinus stenting should not be used for headache alone without visual threat 1.
Headache Management
Headache may persist after intracranial pressure control, requiring separate therapeutic strategies 1, 3. Treatment should follow standard migraine preventive approaches, as the headache phenotype often mimics migraine 1, 2.
Medication overuse headache must be identified and addressed in patients with chronic headache 1.
Monitoring Strategy
Follow-up requires coordinated care between ophthalmology and neurology 5:
- Clinical history and examination remain the cornerstone 5
- Visual field testing is essential 5
- Optical coherence tomography demonstrates structural changes that aid decision-making 5
IIH in ocular remission: Patients whose papilledema has resolved may have ongoing headache morbidity but vision is no longer at risk while papilledema remains absent 1.
Common Pitfalls
- Failing to recognize atypical presentations: Patients outside the typical demographic require more extensive investigation for secondary causes 1
- Treating headache alone with surgery: Surgical interventions should be reserved for visual threat, not isolated headache 1
- Inadequate long-term monitoring: Even after papilledema resolution, patients require ongoing surveillance 1, 5
- Ignoring the role of obesity: Weight management is fundamental to disease modification, not just symptomatic treatment 5, 3