Neurosurgery notes/Vascular/Vascular genetic disease/Sturge–Weber syndrome

Sturge–Weber syndrome

View Details
logo
Parent item
Vascular genetic disease
Definition
  • A rare, congenital neurocutaneous disorder involving the brain, skin & eye,
General
  • AKA
    • Encephalotrigeminal angiomatosis
    • Encephalofacial angiomatoosis
  • Rare sporadic disease
Genetics
  • Most cases are sporadic
  • Somatic mutation in a nucleotide transition in the gene GNAQ (Guanine nucleotide-binding protein G(q) subunit alpha) on chromosome 9q21 that occurs early after conception during in utero development.
Pathology
  • Failure of the primitive cephalic venous plexus to regress in the first trimester
      • notion image
    Diagnostic criteria
    • 2 out of 3 of the following:
      • Facial port-wine birthmark (facial angiomas)
          • notion image
      • Increased intraocular pressure
      • leptomeningeal angiomatosis
        • Patients with only leptomeningeal angiomatosis and no skin or eye involvement are considered to have the intracranial variant of SWS.
          • notion image
          notion image
          notion image
    Subtypes (Roach scale)
    • Type 1: Leptomeningeal plus facial +/- Glaucoma
    • Type 2: facial only +/- Glaucoma
    • Type 3: leptomeningeal only
    Clinical features
    • Cardinal features:
      • Localized cerebral cortical atrophy and calcifications (especially cortical layers 2 and 3, with a predilection for the occipital lobes):
        • Calcifications appear as curvilinear double parallel lines (“tram-tracking”) on plain X-rays
            • notion image
        • Cortical atrophy usually causes contralateral hemiparesis, hemiatrophy, and homonymous hemianopia (with occipital lobe involvement)
      • Ipsilateral port-wine facial nevus (nevus flammeus) usually @ V1 (forehead and/or eyelid) (rarely bilateral):
        • Not always present, alternatively sometimes in V2 or V3 regions
        • 8–20% of patients with facial port-wine birthmarks (with or without ocular involvement) develop neurologic symptoms.
        • Risk of SWS symptoms
          • port-wine stain only in V2 and V3 have a lower risk
          • bilateral V1 birthmarks have a higher risk (≈ 35%)
    • Other findings
      • Ocular involvement
        • Occurs in around 60%
        • Glaucoma
          • most frequent ocular finding
          • may present at any time between birth and the fourth decade.
          • May be unilateral or bilateral, with the latter being more common in patients with bilateral facial PWS.
          • Due to
            • Vascular malformations of the eye in patients with SWS may involve the conjunctiva, episclera, choroid, and retina.
            • Oculomeningeal capillary haemangioma
        • Retinal angiomas
        • Other eye findings include
          • Nevus of Ota
          • Buphthalmos
          • Blindness
          • Coloboma of the iris
      • Neurological deficit
        • Hemiatrophy (possibly from chronic cerebral hypoxia)
        • Progressive hemiparesis 30%,
        • Hemianopsia (40-45%)
      • Seizures
        • Seizures in 1 st year of life (dev. delay)
        • by the age of 5 years: 95%
        • contralateral to the facial nevus and cortical atrophy.
        • Present in most patients starting in infancy
      • Mental retardation or learning disability (50-75%)
      • Migraine like headache (the prevalence in children of < 10 years of age is significantly higher than the general population at 31 versus 5%, respectively)
      • Moyamoya disease
      • Arteriovenous malformation of the lung and liver
      • Endocrinopathies:
        • GH deficiency is more common
          • (18-fold general population)
        • For suspected or confirmed SWS, screen for this in children ≥age 2 years by measuring serum IGF-1
        notion image
      • Arrow showing enlargement of the choroid plexus,
      • Atrophy of the occipital lobe
        • notion image
    Treatment
    • General
      • Treatment is supportive.
      • Aggressive management of fever
        • Flu vaccine
      • Headache: symptomatic treatment
    • Seizures:
      • frequent and protracted seizures exacerbate the neurologic damage.
      • Aim early aggressive treatment of seizures
      • first-line treatment: anticonvulsants
        • oxcarbazepine
          • common initial drug.
          • Side effects include central hypothyroidism, especially in girls
        • levetiracetam &
        • topiramate
      • 2nd line: lobectomy or hemispherectomy
        • For refractory seizures
        • Options include:
          • Functional hemispherectomy
          • Anatomic hemispherectomy
    • Stroke prevention (aspirin, good hydration)
    • Glaucoma: annual ophthalmology check
    • Facial angioma: dermatology referral
    • Skin lesions:
      • laser treatment (currently, flash lamp-pumped PDL is favoured) can lighten the birthmark.
      • May also reduce hypertrophy of soft and bony tissue.
    • Endocrinopathies:
      • Monitor growth and thyroid function
      • Growth hormone deficiency can be replaced; however, there may be a risk of increasing seizures.
    • XRT: complications are common and benefits are lacking.