Department of Neurology, VU University Medical Center, Amsterdam, The Netherlands.
PLoS One. 2010 May 26;5(5):e10839. doi: 10.1371/journal.pone.0010839.
Although epilepsy affects almost 1% of the world population, diagnosis of this debilitating disease is still difficult. The EEG is an important tool for epilepsy diagnosis and classification, but the sensitivity of interictal epileptiform discharges (IEDs) on the first EEG is only 30-50%. Here we investigate whether using 'functional connectivity' can improve the diagnostic sensitivity of the first interictal EEG in the diagnosis of epilepsy.
METHODOLOGY/PRINCIPAL FINDINGS: Patients were selected from a database with 390 standard EEGs of patients after a first suspected seizure. Patients who were later diagnosed with epilepsy (i.e. > or = two seizures) were compared to matched non-epilepsy patients (with a minimum follow-up of one year). The synchronization likelihood (SL) was used as an index of functional connectivity of the EEG, and average SL per patient was calculated in seven frequency bands. In total, 114 patients were selected. Fifty-seven patients were diagnosed with epilepsy (20 had IEDs on their EEG) and 57 matched patients had other diagnoses. Epilepsy patients had significantly higher SL in the theta band than non-epilepsy patients. Furthermore, theta band SL proved to be a significant predictor of a diagnosis of epilepsy. When only those epilepsy patients without IEDs were considered (n = 74), theta band SL could predict diagnosis with specificity of 76% and sensitivity of 62%.
CONCLUSION/SIGNIFICANCE: Theta band functional connectivity may be a useful diagnostic tool in diagnosing epilepsy, especially in those patients who do not show IEDs on their first EEG. Our results indicate that epilepsy diagnosis could be improved by using functional connectivity.
尽管癫痫影响了全球近 1%的人口，但这种致残性疾病的诊断仍然很困难。脑电图是癫痫诊断和分类的重要工具，但首次发作间期癫痫样放电（IEDs）的敏感性仅为 30-50%。在这里，我们研究了使用“功能连接”是否可以提高首次发作间期脑电图在癫痫诊断中的诊断敏感性。
方法/主要发现：从数据库中选择了 390 例首次疑似癫痫发作后患者的标准脑电图患者。将后来被诊断为癫痫（即≥两次发作）的患者与匹配的非癫痫患者（至少随访一年）进行比较。同步可能性（SL）被用作脑电图功能连接的指标，并计算每个患者七个频带的平均 SL。共选择了 114 名患者。57 名患者被诊断为癫痫（20 名患者的脑电图有 IEDs），57 名匹配患者有其他诊断。癫痫患者的 theta 频段 SL 明显高于非癫痫患者。此外，theta 频段 SL 被证明是癫痫诊断的一个显著预测指标。当仅考虑那些没有 IEDs 的癫痫患者（n=74）时，theta 频段 SL 可以预测诊断的特异性为 76%，敏感性为 62%。
结论/意义：theta 频段功能连接可能是诊断癫痫的有用工具，尤其是在那些首次脑电图无 IEDs 的患者中。我们的结果表明，通过使用功能连接可以改善癫痫诊断。
