What is the prognosis of PWS in Sturge-Weber syndrome (SWS)?

Updated: Dec 26, 2018
  • Author: Masanori Takeoka, MD; Chief Editor: George I Jallo, MD  more...
  • Print
Answer

Facial nevi are congenital macular lesions that can be progressive; they may be a light pink color initially and then progress to a dark red or purple nodular lesion. These may be isolated to the skin, associated with lesions in the choroidal vessels of the eye or the leptomeningeal vessels of the brain, or even located on other body areas. [33] A facial nevus, or PWS may be difficult to visualize in a patient with dark skin pigmentation.

Not all people with a PWS have SWS; the overall incidence of SWS has been reported to be 8-33% in individuals with a PWS. Several studies have evaluated this specifically.

A study by Enjolras et al indicated that in patients with a PWS, SWS occurs only when the nevus involves the V1 (ophthalmic) distribution of the trigeminal nerve. In their retrospective review, the investigators studied data from 106 patients with a facial PWS, 12 of whom had SWS and 4 of whom had glaucoma without pial lesions. No patients who had involvement of the V2 (maxillary) and/or V3 (mandibular) area without V1 involvement had SWS. [32]

Patients in the study who were considered to be at high risk for SWS were those with involvement of the entire V1 area; 11 of 25 patients with full V1 involvement had SWS. Patients with only partial involvement of V1 were at low risk (only 1 of 17 patients had SWS).

In a study of 121 patients with facial nevi affecting the skin in the distribution of the trigeminal nerve, Bioxeda et al concluded that only those persons with V1 involvement were at risk for epilepsy or glaucoma. The investigators found that glaucoma and epilepsy were present in 23 (17%) and 17 (14%) patients, respectively, with V1 involvement occurring in all 40 of these individuals. [34]

The investigators also found that the facial nevi were located predominantly over the distribution of the V2 branch of the trigeminal nerve in 88% of these individuals, either isolated to the V2 branch or also involving the V1 and/or V3 branches. An extrafacial PWS was more common when V3 was involved. The lesions were unilateral in 86% of patients, and bilateral in 14% of them.

In a similar, but larger, study, Tallman et al found that only patients with a PWS involving the distributions of the V1 and V2 branches of the trigeminal nerve had CNS or eye involvement. The investigators reported on 310 patients with facial nevi, 85% of who had unilateral involvement, 15% of whom had bilateral involvement, and 68% of who had involvement of more than 1 dermatome. Overall, in patients with trigeminal involvement, only 8% had CNS and eye involvement; 24% of those with bilateral lesions had eye or CNS involvement, compared with only 6% of patients with unilateral lesions. [35]

Tallman and colleagues also found that all patients with eye or CNS involvement had lesions on the eyelids; 91% of these had both upper and lower eyelid involvement, whereas 9% had only lower eyelid involvement. No patients with upper eyelid involvement alone had eye or CNS involvement. Three of 16 patients with involvement of V1, V2, and V3 had eye and/or CNS involvement. The authors recommended screening for glaucoma and CNS involvement when the PWS involved the eyelids, with unilateral V1, V2, and V3 lesions, or with bilateral lesions.

Patients identified by the Sturge-Weber Foundation had a different pattern of involvement—170 of 171 patients had a craniofacial PWS, with unilateral involvement in 83 patients (49%) and bilateral involvement in 86 patients (51%).

Note that an extrafacial PWS may have associated intracranial abnormalities; for example, in Klippel-Trenaunay-Weber syndrome, neuroimaging may show findings similar to those of SWS, [36] and a cervical PWS has been associated with occipital calcifications. [33]


Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!