Detection of cortical arousals in children using frontal EEG leads in addition to conventional central leads.

STUDY OBJECTIVE This study was designed to assess the efficacy of using Fz as an additional electrode in screening arousals during polysomnography in children. METHODS Polysomnograms from 24 children were randomly selected from a sleep-study database of children from different diagnostic categories. Of the children whose polysomnograms selected, 5 were normal, 5 had severe obstructive sleep apnea syndrome, 5 had mild obstructive sleep apnea syndrome, 5 had snoring, and 4 had periodic limb movement disorder. American Academy of Sleep Medicine criteria for arousal were applied to Fz only, C3/C4 only, or both electrode sites combined. RESULTS C3/C4 electrode sites picked up 96.33% of arousals in the polysomnograms of children, compared with 87.46% arousals identified at Fz. An additional 3.3% of arousals were identified at Fz that were not detected at C3/C4. The average median number of arousals per subject, accompanied by the interquartile range, was 29 (19.2-39.7) at C3/C4 and 27.5 (19.2-33.7) at FZ, reflecting a significant difference between the two (p = .005). The use of both electrodes sites resulted in the detection of the highest number of arousals per subject, with a median of 29 (20.2-40.7). CONCLUSION Unlike findings recently reported in adults, our study detected a higher number of arousals from central electrodes rather than frontal, with the maximum number of arousals obtained using a combination of frontal and central electrodes. A possible explanation for differences in the optimal location for detection of arousals between adults and children is discussed.