Quantitative EEG Asymmetry Correlates with Clinical Severity in Unilateral Sturge‐Weber Syndrome

• Published in: Epilepsia (Copenhagen) Vol. 48; no. 1; pp. 191 - 195
• Main Authors: Hatfield, Laura A., Crone, Nathan E., Kossoff, Eric H., Ewen, Joshua B., Pyzik, Paula L., Lin, Doris D. M., Kelley, Thomas M., Comi, Anne M.
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01-01-2007; Blackwell
• Subjects: Adolescent; Adult; Biological and medical sciences; Brain Mapping; Cerebral Cortex - physiopathology; Child; Child, Preschool; Clinical severity; Complex syndromes; Disease Progression; Electrodiagnosis. Electric activity recording; Electroencephalography - statistics & numerical data; Epilepsy - diagnosis; Epilepsy - physiopathology; Female; Fourier Analysis; Functional Laterality - physiology; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; Humans; Infant; Investigative techniques, diagnostic techniques (general aspects); Magnetic Resonance Imaging - statistics & numerical data; Male; Medical genetics; Medical sciences; Monitoring, Physiologic; Nervous system; Nervous system (semeiology, syndromes); Neurology; Quantitative EEG; Severity of Illness Index; Sturge-Weber Syndrome - diagnosis; Sturge-Weber Syndrome - physiopathology; Sturge‐Weber syndrome; Skin disease; Nervous system diseases; Epilepsy; Electrophysiology; Cardiovascular disease; Electroencephalography; Sturge Weber Krabbe disease; Cerebral disorder; Vascular disease; Angioma; Asymmetry; Malformation; Central nervous system disease; Sturge-Weber syndrome-Quantitative EEG-Clinical severity
• ISSN: 0013-9580; 1528-1167
• DOI: 10.1111/j.1528-1167.2006.00630.x

Purpose: Sturge‐Weber syndrome (SWS) is a neurocutaneous disorder with vascular malformations of the skin, brain, and eye. SWS results in ischemic brain injury, seizures, and neurologic deficits. We hypothesized that a decrease in quantitative EEG (qEEG) power, on the affected side, correlates with clinical severity in subjects with SWS.
Methods: Fourteen subjects had 16‐channel scalp EEG recordings. Data were analyzed using fast Fourier transform and calculation of power asymmetry. Blinded investigators assigned scores for clinical neurological status and qualitative assessment of MRI and EEG asymmetry.
Results: The majority of subjects demonstrated lower total power on the affected side, usually involving all four frequency bands (delta, theta, alpha, and beta). qEEG asymmetry correlated strongly with neurologic clinical severity scores and MRI asymmetry scores. qEEG data generally agreed with the MRI evidence of regional brain involvement. In MRI‐qEEG comparisons that did not agree, decreased power on qEEG in a brain region not affected on MRI was more likely to occur in subjects with more severe neurologic deficits.
Conclusions: qEEG provides an objective measure of EEG asymmetry that correlates with clinical status and brain asymmetry seen on MRI. These findings support the conclusion that qEEG reflects the degree and extent of brain involvement and dysfunction in SWS. qEEG may potentially be a useful tool for early diagnosis and monitoring of disease progression in SWS. qEEG may prove useful, in severely affected individuals with SWS, for determining regions of brain dysfunction.