Idiopathic Intracranial Hypertension
This article provides a comprehensive overview of Idiopathic Intracranial Hypertension (IIH), also known as pseudotumor cerebri. It discusses the symptoms, diagnostic procedures, and various treatment approaches for IIH, highlighting the condition's prevalence in overweight women of childbearing age and its potential for severe, disabling headaches and vision loss.
Introduction to IIH (Pseudotumor Cerebri)
IIH is a disorder characterized by symptoms and signs of increased intracranial pressure, such as headache, papilledema, and vision loss, with normal cerebrospinal fluid composition and no evident cause on neuroimaging. IIH primarily affects overweight women of childbearing age and can lead to intractable headaches and severe vision loss. Idiopathic intracranial hypertension (IIH) (pseudotumor cerebri) is a disorder that includes symptoms and signs of increased intracranial pressure (headache, papilledema, vision loss), with normal cerebrospinal fluid composition, and no other cause of intracranial hypertension evident on neuroimaging. IIH primarily affects women of childbearing age who are overweight. Many patients suffer from intractable, disabling headaches, and there is a risk of severe, permanent vision loss. Even patients with mild vision loss have an associated reduction in their quality of life. Brain magnetic resonance imaging (MRI) and MR venography (MRV) are the preferred images.
Lifestyle Modification and Medication
Any potential agent that might cause or worsen IIH, such as, tetracyclin, should be discontinued. Treatment includes weight reduction programs, medical treatment for IIH, medical treatment of headache, surgical intervention and follow- up. A low- sodium weight reduction program is recommended for all obese patients with IIH and appears to alleviate symptoms and signs in many but not all patients. Medically supervised weight loss programs or surgically induced weight reduction (gastric banding or gastric bypass procedures) may be necessary in morbidly obese patients.
Specific Medical Treatments for IIH
Medical treatment for IIH is with carbonic anhydrase inhibitors. They include acetazolamide (500 mg twice per day and advance the dose as required up to 2-4 grams per day, as tolerated by the patient). In patients unable to tolerate acetazolamide, topiramate (25 mg daily), or methazolamide (50 mg daily) is considered. Also, loop diuretics (furosemide 20-40 mg daily) may be used as an adjunctive therapy. Glucocorticoids are not recommended for most patients with IIH. Also, patients with IIH who continue to have headaches despite improvement in papilledema and visual function may require additional medications including valproate (10- 15 mg/kg/day).
Surgical Interventions
The two main surgical procedures in IIH are optic nerve sheath fenestration (ONSF) and cerebrospinal fluid (CSF) shunting procedures. Surgical treatment is indicated in patients with IIH who fail, intolerant to, or are noncompliant with maximum medical treatment and have intractable headache or progressive visual loss. The choice of surgical procedure is individualized based upon available expertise and patient preference.
Follow-Up and Monitoring
Then, patients require regular follow- up visits until they stabilize. Each office visit should include a best corrected visual acuity, formal visual field testing, and dilated fundus examination with optic disc photographs. Also, patients should be questioned regarding symptoms of sleep apnea; diagnostic polysomnography and treatment of sleep apnea should follow where appropriate.
References
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