Sturge–Weber syndrome

Overview

Sturge–Weber syndrome (SWS), also known as encephalotrigeminal angiomatosis, is a rare congenital neurocutaneous disorder characterized by vascular malformations affecting the skin, brain, and eyes. The hallmark feature is a facial port-wine stain (nevus flammeus), typically involving the ophthalmic (V1) branch of the trigeminal nerve. Associated abnormalities include leptomeningeal angiomas—abnormal blood vessels on the brain surface—and ocular complications such as glaucoma.

SWS is a sporadic condition that affects approximately 1 in 20,000 to 50,000 live births. It manifests with neurological, dermatological, and ophthalmologic symptoms and can vary widely in severity and clinical presentation.

Causes

Sturge–Weber syndrome is caused by a somatic activating mutation in the GNAQ gene, which encodes a G protein involved in cell signaling pathways regulating vascular development. This mutation occurs after fertilization, leading to mosaicism where only some cells carry the mutation. This explains the patchy distribution of vascular malformations.

Because the mutation is somatic and mosaic, SWS is not inherited and occurs sporadically without family history.

Symptoms

The clinical presentation of Sturge–Weber syndrome varies but commonly includes:

Cutaneous Symptoms

• Facial port-wine stain (a reddish to purplish birthmark), usually unilateral and involving the forehead and upper eyelid

• Possible extension to other parts of the face or body in rare cases

Neurological Symptoms

• Seizures, often starting in infancy

• Hemiparesis (weakness on one side of the body)

• Developmental delays or intellectual disability

• Headaches and stroke-like episodes

• Leptomeningeal angiomas seen on brain imaging

Ocular Symptoms

• Glaucoma, which can lead to vision loss

• Choroidal hemangiomas (vascular tumors in the eye)

• Visual field defects

Diagnosis

Diagnosis of Sturge–Weber syndrome is clinical, supported by imaging and ophthalmologic evaluation:

• Clinical examination: Identification of facial port-wine stain and neurological signs.

• Neuroimaging: MRI with contrast to detect leptomeningeal angiomas and brain calcifications.

• Ophthalmologic assessment: Evaluation for glaucoma and choroidal abnormalities.

• Electroencephalogram (EEG): To assess seizure activity.

• Genetic testing: Identification of somatic GNAQ mutations in affected tissues (not routine but available in specialized centers).

Treatment

There is no cure for Sturge–Weber syndrome, and treatment focuses on symptom management and complication prevention:

Seizure Management

• Antiepileptic medications to control seizures

• In refractory cases, surgical interventions such as hemispherectomy may be considered

Ocular Treatment

• Glaucoma management with medications or surgery

• Monitoring and treatment of choroidal hemangiomas

Dermatologic Care

• Laser therapy (pulsed dye laser) to lighten port-wine stains

• Cosmetic and psychological support

Supportive Care

• Physical, occupational, and speech therapy for developmental delays and hemiparesis

• Regular neurological and ophthalmological follow-up

Prognosis

The prognosis of Sturge–Weber syndrome varies based on the extent and severity of brain and eye involvement. Early-onset seizures and extensive leptomeningeal angiomas are associated with poorer neurological outcomes. Glaucoma can lead to irreversible vision loss if untreated.

With modern multidisciplinary care, many individuals achieve improved seizure control and better quality of life. Ongoing research into targeted therapies offers hope for future advances in managing this complex disorder.