Intracranial hypertension syndrome

Overview

Intracranial hypertension syndrome, also known as increased intracranial pressure (ICP), refers to a condition in which the pressure inside the skull rises beyond normal levels. This pressure buildup can affect the brain’s function and structure, potentially leading to serious neurological complications if left untreated. Intracranial hypertension can be classified into two types: secondary intracranial hypertension, caused by an identifiable condition such as trauma or a tumor, and idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, where no clear cause is found. IIH is more common in overweight women of childbearing age.

Causes

The causes of intracranial hypertension depend on whether the condition is primary (idiopathic) or secondary:

Secondary Intracranial Hypertension:

• Brain tumors or abscesses

• Traumatic brain injury

• Hydrocephalus: Abnormal buildup of cerebrospinal fluid (CSF)

• Stroke or brain hemorrhage

• Meningitis or encephalitis

• Venous sinus thrombosis

• Certain medications: Such as tetracyclines, growth hormone, or excessive vitamin A

Idiopathic Intracranial Hypertension (IIH):

• No identifiable cause, though associated with:

  • Obesity

  • Female sex (especially childbearing age)

  • Endocrine changes (e.g., pregnancy, contraceptive use)

Symptoms

Symptoms of intracranial hypertension are related to increased pressure on the brain and the optic nerves. Common signs include:

• Severe headache: Often worse in the morning or when lying down

• Visual disturbances: Blurred vision, double vision (diplopia), or transient visual obscurations

• Papilledema: Swelling of the optic disc, visible on eye examination

• Nausea and vomiting

• Neck or shoulder stiffness

• Pulsatile tinnitus: Hearing a rhythmic whooshing sound in the ears

• Photophobia or sensitivity to light

• In severe cases: Confusion, drowsiness, or loss of consciousness

Diagnosis

Diagnosing intracranial hypertension requires clinical evaluation, imaging, and pressure measurement:

• Neurological exam: To assess cranial nerve function and check for signs like papilledema

• Ophthalmologic exam: Fundoscopy to detect optic disc swelling

• Imaging studies: MRI or CT scan to rule out structural causes (e.g., tumors, hydrocephalus)

• Magnetic resonance venography (MRV): Especially important for identifying venous sinus thrombosis

• Lumbar puncture (spinal tap): Measures cerebrospinal fluid (CSF) pressure and analyzes fluid for infection or inflammation

Treatment

Treatment depends on the underlying cause and severity of symptoms:

For Secondary Intracranial Hypertension:

• Treat the underlying condition: Such as tumor removal, antibiotics for infections, or anticoagulation for venous thrombosis

• CSF drainage: Via lumbar puncture or surgically placed shunt to relieve pressure

For Idiopathic Intracranial Hypertension (IIH):

• Weight loss: Especially in overweight patients; even modest weight reduction can improve symptoms

• Medications:

  • Acetazolamide: First-line treatment to reduce CSF production

  • Furosemide: Sometimes used in combination for added effect

  • Topiramate: May aid in weight loss and reduce CSF pressure

• Repeated lumbar punctures: Temporary relief in severe or urgent cases

• Optic nerve sheath fenestration: A surgical procedure to relieve pressure and prevent vision loss

• CSF shunt surgery: Placement of a shunt to continuously drain excess fluid in refractory cases

Prognosis

The prognosis of intracranial hypertension varies depending on the underlying cause and promptness of treatment:

• Secondary ICH: Prognosis depends on how quickly and effectively the cause is treated. Delay can lead to permanent brain damage or death.

• Idiopathic ICH: Many patients improve with weight loss and medical therapy. However, if left untreated, it can result in progressive vision loss or blindness.

With early diagnosis and proper management, most patients can achieve good long-term outcomes and prevent serious complications.