Idiopathic Intracranial Hypertension

Terminology and Synonyms

Idiopathic intracranial hypertension (IIH) and pseudotumor cerebri are interchangeable terms referring to the same clinical condition, as stated by the American College of Radiology 1, 2
Primary PTCS is specifically known as idiopathic intracranial hypertension, according to the American College of Radiology 3

Visual disturbances including papilledema are characteristic of IIH/pseudotumor cerebri, as noted by the American College of Radiology 3

Most commonly affects overweight females of childbearing age, as reported by the American College of Radiology 3, 4
Can also occur in obese males and prepubertal thin girls and boys, according to the American College of Radiology 3
The incidence is rising in parallel with the obesity epidemic, as stated by the American College of Radiology 3

Normal neuroimaging (absence of mass, hydrocephalus, or abnormal meningeal enhancement) is a diagnostic criterion, as stated by Praxis Medical Insights 4
Normal cerebrospinal fluid composition is a diagnostic criterion, according to Praxis Medical Insights 4
Elevated lumbar puncture opening pressure (>280 mm CSF in children or >250 mm CSF in non-sedated, non-obese children) is a diagnostic criterion, as reported by the American College of Radiology 5
Papilledema is typically present but not always required for diagnosis, as noted by Praxis Medical Insights 4

MRI may show secondary signs of increased intracranial pressure, including empty sella, as reported by the American College of Radiology 3
MRI may show secondary signs of increased intracranial pressure, including dilated optic sheaths, according to the American College of Radiology 3
MRI may show secondary signs of increased intracranial pressure, including tortuous or enhancing optic nerves, as noted by the American College of Radiology 3
MRI may show secondary signs of increased intracranial pressure, including flattening of the posterior aspects of the globes, as reported by the American College of Radiology 3, 5
MRI may show secondary signs of increased intracranial pressure, including transverse sinus stenosis, according to the American College of Radiology 5

Proposed mechanisms include impaired cerebrospinal fluid homeostasis, as reported by the American College of Radiology 3
Proposed mechanisms include altered venous hemodynamics, according to the American College of Radiology 3
Proposed mechanisms include reduced cerebral drainage through the internal jugular vein, as noted by the American College of Radiology 3
Proposed mechanisms include increased intracranial CSF volume accumulating in the subarachnoid space, as stated by the American College of Radiology 3

Secondary PTCS can result from cerebral venous abnormalities such as thrombosis, as reported by the American College of Radiology 3
Secondary PTCS can result from medications (vitamin A, retinoids, steroids, etc.), according to the American College of Radiology 3
Secondary PTCS can result from endocrine disorders, as noted by the American College of Radiology 3, 5

Blood pressure measurement is a mandatory part of the initial evaluation of patients with suspected IIH to exclude malignant hypertension as a cause of papilledema, as recommended by the American Academy of Neurology 6

Topiramate may help with weight loss by suppressing appetite and can reduce intracranial pressure through carbonic anhydrase inhibition, with a treatment failure rate of worsening vision after stabilization in 34% of patients at 1 year and 45% at 3 years 7

Follow-up intervals should be based on papilledema grade and visual field status, with more frequent monitoring needed for severe or worsening cases, and patients with IIH often develop migrainous headaches superimposed on headaches from raised intracranial pressure, requiring specific treatment approaches 8
Proper blood pressure control remains important in the overall management of IIH patients, although hypertension is not specifically identified as a worsening factor for IIH in current guidelines 6