Retrospective review of screening for Sturge-Weber syndrome with brain magnetic resonance imaging and electroencephalography in infants with high-risk port-wine stains

Background: There is a lack of consensus regarding how best to screen children with facial port-wine stains for Sturge-Weber syndrome. Many favor brain magnetic resonance imaging, and adjunctive electroencephalography is increasingly used. However, the sensitivity, specificity, and negative and positive predictive value of magnetic resonance imaging and electroencephalography and whether screening improves seizure recognition is unclear. Methods: A retrospective review of children with high-risk port-wine stains presenting consecutively to the outpatient laser clinic of a tertiary pediatric hospital between December 2015 and November 2016 was undertaken. Primary outcome measures were yield, accuracy, age of and protocols for screening magnetic resonance imaging and electroencephalography, type of and age at presenting seizure, and percentage referred to neurology. Results: Of 126 patients with facial port-wine stains, 25.4% (32/126) were at high risk of Sturge-Weber syndrome (hemifacial, median, and forehead PWS phenotypes); 43.7% of these (14/32) underwent screening magnetic resonance imaging. Sturge-Weber syndrome was detected in 7.1% (1/14). Magnetic resonance imaging had false-negative results in 23.1% (3/13) of those screened. Screening magnetic resonance imaging had sensitivity of 25%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 76.9% for the detection of Sturge-Weber syndrome (hemifacial, median and forehead PWS phenotypes). Only one-third of those with false-negative magnetic resonance imaging were referred to neurology. Mean age of first seizure in those with false-negative screening magnetic resonance imaging was 28 months, vs 14 months in those not screened. Abnormal electroencephalographic signs were detected in the two infants who underwent presymptomatic electroencephalography. Conclusions: Findings from this small cohort of individuals with port-wine stains that put them at high risk of Sturge-Weber syndrome suggest that children with positive screening magnetic resonance imaging will almost certainly develop Sturge-Weber syndrome but that negative screening magnetic resonance imaging cannot exclude Sturge-Weber syndrome (in up to 23.1% of cases). False-negative magnetic resonance imaging may delay seizure recognition. Seizure education, monitoring, and consideration of adjunctive electroencephalography are important irrespective of magnetic resonance imaging findings.