Summary
Sturge-Weber syndrome (SWS) is a congenital vascular malformation characterised by facial capillary malformations (classically referred to as angiomas even through they are not tumours), accompanied by variable degrees of ocular and neurological anomalies. The estimated incidence is 1 in 50 000. The facial angioma is a port-wine stain (PWS) that is generally present at birth and located on the forehead or upper eyelid (V1 zone). The PWS is sometimes more extensive, covering also, uni- or bilaterally, the V2 (maxillary) and V3 (mandibular) areas of the face, and in some cases extending to the trunk and limbs. In rare cases, there is no facial capillary malformation but cerebral vascular malformations are present and are similar to those found in cases of typical SWS. More than half of the patients with SWS develop glaucoma on the same side of the face as the V1 zone PWS, particularly if the PWS is located on either the upper or lower eyelid. Glaucoma and vascular anomalies have also be reported in the fundus in certain cases. Patients also present with leptomeningeal vascular anomalies, which may be responsible for the comitial crises (usually occurring before 2 years of age and reported in 75% of patients with intracranial vascular anomalies), and varying degrees of contralateral motor deficit and leaning disability. The psychomotor deterioration is variable, depending, in part, on potential problems concerning medical management of the epilepsy. As the disease progresses, ipsilateral cerebral haemiatrophy occurs together with the appearance of cortical calcifications delineating the cerebral gyri. SWS is a non-hereditary syndrome of unknown aetiology. It is hypothesised to be caused by somatic mutations affecting the anterior neural primodium before migration of the cephalic neural crests. Diagnosis is made at birth on the basis of the presence of neurological manifestations and a facial V1 zone PWS. Approximately 10% of infants with a V1 zone PWS have SWS. Neurological lesions in SWS can be investigated by skull radiography (calcifications are rarely present in newborns), electroencephalogram and most commonly computed tomography (CT) scan with iodinated contrast injection or better still, magnetic resonance imaging (MRI) with gadolinium injection (allowing earlier collection of more detailed data than those obtained by CT scan). When possible, functional cerebral imagining is useful and should be performed as part of the neuroradiological evaluation (cerebral blood flow measurement using the Xenon-133 inhalation technique, single photon emission computed tomography (SPECT) analysis of cerebral metabolism by measuring glucose consumption, or positron emission tomography (PET)). SWS is a neuropaediatric medical emergency and treatment is symptomatic. Pulse-laser therapy can be used to treat the PWS in SWS patients in which the epilepsy is being treated and controlled by anti-convulsants. The risk of glaucoma is high and frequent ophthalmologic examinations should be carried out during the first two years of life. Ophthalmologic follow-up should continue until adulthood, even if the early examinations give normal results. Surgery may be recommended in case of glaucoma. Severe muscular weakness also needs management. The prognosis depends mainly on the frequency and severity of the epileptic crises, which often begin during the first year of life and may lead to paralysis of certain parts of the body and mild to severe intellectual deficit. Neurosurgical intervention is required only in exceptional cases. *Author: Dr O. Enjolras (May 2006)*.
