Encephalotrigeminal Angiomatosis

Encephalotrigeminal Angiomatosis

Encephalotrigeminal Angiomatosis, also known as Sturge-Weber syndrome, is a rare congenital disorder characterized by the presence of a facial capillary malformation known as a port-wine stain, neurological abnormalities, and ocular manifestations. This condition is part of a group of disorders called phakomatoses, which are characterized by the involvement of the skin and nervous system.

Clinical Features

The hallmark of Encephalotrigeminal Angiomatosis is the presence of a port-wine stain, typically located on the forehead and upper eyelid, following the distribution of the trigeminal nerve. This vascular malformation is due to an overabundance of capillaries near the surface of the skin.

Neurological symptoms are a significant aspect of the syndrome. These may include:

• Seizures: Often the first neurological sign, seizures can vary in type and severity. They usually begin in infancy and may be difficult to control.
• Hemiparesis: Weakness on one side of the body, often correlating with the side of the brain affected by the leptomeningeal angioma.
• Developmental Delays: Cognitive impairment and learning disabilities are common.
• Headaches: Chronic headaches may occur due to increased intracranial pressure.

Ocular involvement can include:

• Glaucoma: Increased intraocular pressure can lead to vision loss if untreated.
• Choroidal Hemangiomas: These can cause visual field defects and retinal detachment.

Pathophysiology

Encephalotrigeminal Angiomatosis is caused by a somatic mutation in the GNAQ gene, which leads to abnormal blood vessel development. The mutation occurs after fertilization, resulting in a mosaic pattern of affected and unaffected tissues.

The leptomeningeal angiomas, which are abnormal blood vessels on the surface of the brain, are responsible for the neurological symptoms. These angiomas can cause chronic ischemia and hypoxia, leading to cortical atrophy and calcification.

Diagnosis

Diagnosis is primarily clinical, based on the presence of the characteristic port-wine stain and neurological symptoms. Imaging studies such as MRI and CT scan are used to identify leptomeningeal angiomas and calcifications. An ophthalmologic examination is essential to assess for glaucoma and other ocular abnormalities.

Management

Management of Encephalotrigeminal Angiomatosis is symptomatic and supportive. It includes:

• Seizure Control: Antiepileptic drugs are used to manage seizures. In some cases, surgical intervention may be necessary.
• Glaucoma Treatment: This may involve medications, laser therapy, or surgery to reduce intraocular pressure.
• Laser Therapy: Pulsed dye laser treatment can lighten the port-wine stain.
• Rehabilitation Services: Physical, occupational, and speech therapy can help manage developmental delays and hemiparesis.

Prognosis

The prognosis for individuals with Encephalotrigeminal Angiomatosis varies widely. Early diagnosis and management of symptoms can improve quality of life. However, the condition can lead to significant neurological impairment and vision loss.

Also see

• Phakomatoses
• Port-wine stain
• Leptomeningeal angioma
• GNAQ gene