From the Guidelines
Pseudotumor cerebri, also known as idiopathic intracranial hypertension (IIH), is a condition characterized by increased pressure around the brain without a tumor or other disease, typically manifesting as severe headaches and visual impairments, and prevailing in overweight females of childbearing age.
Definition and Diagnosis
Pseudotumor cerebri is a disorder that mimics the symptoms of a brain tumor, but without the presence of an actual tumor. The condition is also known as idiopathic intracranial hypertension (IIH) and is characterized by increased pressure around the brain, leading to symptoms such as headaches, pulsatile tinnitus, transient visual obscurations, and papilledema (swelling of the optic nerve) 1. The diagnosis of pseudotumor cerebri is based on the presence of papilledema, normal neurological examination, normal brain parenchyma on imaging, normal cerebrospinal fluid composition, and elevated lumbar puncture opening pressure 1.
Causes and Risk Factors
The exact cause of pseudotumor cerebri is unclear, but it is thought to be related to impaired cerebrospinal fluid (CSF) homeostasis and altered venous hemodynamics 1. The condition is more common in overweight females of childbearing age, but it can affect anyone. Secondary causes of pseudotumor cerebri include cerebral venous anomalies, intracranial arteriovenous fistulas, medications, and endocrine disorders 1.
Symptoms and Treatment
Symptoms of pseudotumor cerebri typically include headaches, pulsatile tinnitus, transient visual obscurations, and papilledema. Treatment usually begins with weight loss for overweight patients, as even modest weight reduction can improve symptoms. The first-line medication is acetazolamide (Diamox), which reduces cerebrospinal fluid production. Topiramate (25-100 mg twice daily) serves as an alternative that offers the dual benefit of CSF reduction and weight loss. For severe or rapidly progressing vision loss, lumbar punctures to remove fluid may provide temporary relief. Surgical interventions like optic nerve sheath fenestration or CSF shunting procedures are reserved for patients with progressive vision loss despite medical therapy 1.
Importance of Prompt Treatment
Prompt treatment is crucial to prevent permanent visual impairment, which is the main risk of pseudotumor cerebri. Regular monitoring of visual fields and optic nerve appearance is essential to ensure that the condition is properly managed. With proper treatment, most patients with pseudotumor cerebri can experience significant improvement in their symptoms and quality of life.
From the Research
Definition and Characteristics of Pseudotumor Cerebri
- Pseudotumor cerebri, also known as idiopathic intracranial hypertension (IIH), is a syndrome of elevated intracranial pressure of unknown cause that occurs predominantly in obese women of childbearing age 2.
- It is characterized by symptoms and signs of increased intracranial pressure, including papilledema, headache, visual symptoms, and pulsatile tinnitus 3, 4.
- The diagnosis of pseudotumor cerebri is one of exclusion, and other causes of increased intracranial pressure must be ruled out through history, imaging, and cerebrospinal fluid examination 2.
Clinical Presentation and Complications
- Typical features of pseudotumor cerebri include headache, visual symptoms, and pulsatile tinnitus, with cranial nerve deficits seen in a minority of cases 3.
- If left untreated, papilledema can cause progressive irreversible visual loss and optic atrophy 2.
- In some cases, pseudotumor cerebri can be complicated by diffuse ophthalmoparesis and polyradiculopathy, which can rapidly improve with treatment 3.
Treatment Options
- Medical management includes weight reduction, pharmaceuticals that reduce cerebrospinal fluid production, and lumbar punctures to reduce intracranial pressure 2, 5, 4.
- Acetazolamide is a common medical treatment for pseudotumor cerebri, and other medical treatments can be added or substituted if necessary 2, 6.
- Surgical interventions, such as optic nerve sheath fenestration or cerebrospinal fluid shunting, may be required in cases of severe or rapidly progressive visual loss 2, 3, 5.
- Endovascular stenting of stenotic dural sinuses is also being explored as a treatment option for pseudotumor cerebri, particularly in cases with venous disease 6.