PMID- 26690549
OWN - NLM
STAT- MEDLINE
DCOM- 20170105
LR  - 20220330
IS  - 1537-1603 (Electronic)
IS  - 0736-0258 (Linking)
VI  - 33
IP  - 2
DP  - 2016 Apr
TI  - Burst-Suppression Ratio on Electrocorticography Depends on Interelectrode 
      Distance.
PG  - 127-32
LID - 10.1097/WNP.0000000000000248 [doi]
AB  - INTRODUCTION: With deepening of anesthesia-induced comatose states, the EEG 
      becomes fragmented by increasing periods of suppression. When measured from 
      conventional EEG recordings, the binary burst-suppression signal (BS) appears 
      similar across the scalp. As such, the BS ratio (BSR), quantifying the fraction 
      of time spent in suppression, is clinically considered a global index of brain 
      function in sedation monitoring. Recent studies indicate that BS may be 
      considerably asynchronous when measured with higher spatial resolution such as on 
      electrocorticography. The authors investigated the magnitude of BSR changes with 
      cortical recording interelectrode distance. METHODS: The authors selected 
      fronto-parietal electrocorticography recordings showing propofol-induced BS 
      recorded via 8-electrode strips (1-cm interelectrode distance) during cortical 
      motor mapping in 31 patients. For 1-minute epochs, bipolar recordings were 
      computed between each electrode pair. The median BSR, burst duration (BD), and 
      bursting frequency were derived for each interelectrode distance. RESULTS: At 
      1-cm interelectrode distance, with increasing BSR, BD decreased exponentially. 
      For a BSR between 50% and 80%, BD reached a plateau of 2.1 seconds while the 
      bursting frequency decreased from 14 to 6 bursts per minute. With increasing 
      interelectrode distance, BD increased at a rate of 0.2 seconds per cm. This 
      correlated with a decrease in BSR with distance that reached the rate of -4.4 
      percentage per centimeters during deepest anesthesia. CONCLUSIONS: With 
      increasing cortical interelectrode recording distance, burst summation leads to 
      an increasing BD associated with a reduction in BSR. Standardization of 
      interelectrode distance is important for cortical BSR measurements.
FAU - Moldovan, Mihai
AU  - Moldovan M
AD  - *Division of Physiology and Neuroscience, Department of Functional Sciences, 
      "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania; 
      daggerDepartment of Neuroscience and Pharmacology, University of Copenhagen, 
      Copenhagen, Denmark; double daggerIntraoperative Neurophysiology Unit, Department of 
      Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, 
      Massachusetts;  section signDepartment of Pharmacology, University of Oxford, Oxford, United 
      Kingdom; and  ||Department of Neurology, University Hospitals Case Medical Center, 
      Cleveland, Ohio.
FAU - Calin, Alexandru
AU  - Calin A
FAU - Kumaraswamy, Vishakhadatta M
AU  - Kumaraswamy VM
FAU - Braver, Diana
AU  - Braver D
FAU - Simon, Mirela V
AU  - Simon MV
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Clin Neurophysiol
JT  - Journal of clinical neurophysiology : official publication of the American 
      Electroencephalographic Society
JID - 8506708
SB  - IM
MH  - Brain Mapping/methods
MH  - Electrocorticography/*methods/standards
MH  - *Electrodes
MH  - Female
MH  - Humans
MH  - Male
MH  - Middle Aged
MH  - Retrospective Studies
EDAT- 2015/12/23 06:00
MHDA- 2017/01/06 06:00
CRDT- 2015/12/23 06:00
PHST- 2015/12/23 06:00 [entrez]
PHST- 2015/12/23 06:00 [pubmed]
PHST- 2017/01/06 06:00 [medline]
AID - 10.1097/WNP.0000000000000248 [doi]
PST - ppublish
SO  - J Clin Neurophysiol. 2016 Apr;33(2):127-32. doi: 10.1097/WNP.0000000000000248.