Siddiqi Maria, Ahmed S Nizam
a Division of Neurology, Department of Medicine , University of Alberta , Edmonton , Canada.
b Clinical Neurophysiology Laboratory, Division of Neurology, Department of Medicine , University of Alberta , Edmonton , Canada.
Neurodiagn J. 2017;57(3):211-223. doi: 10.1080/21646821.2017.1353799.
This study aimed at evaluating the value added by 24-hour ambulatory EEG (AEEG) by comparing the presence of epileptiform discharges (EDs) between the first 30 minutes of recording versus the following 23.5 hours.
A retrospective review of AEEGs of subjects divided into two groups, epilepsy and undiagnosed episodes of loss of consciousness, was conducted. AEEGs were divided into early EEG (E-EEG) (first 30 minutes) and extended EEG (remaining 23.5 hours). Extended EEGs were further divided into segments (S): 31st minute to 8th hour (SI), 9th to 16th hours (SII) and 17th to 24th hours (SIII). Each consecutive segment was reviewed to identify new EDs not seen previously.
Fifty-seven AEEGs were included, the median age being 36.3 years, the range being 18.7 to 78.6 years. There were 38 (66.6%) females. The collective yield of AEEG for detecting EDs was 19/57 (33.4%). The yield of E-EEG of new EDs was 5/57 (9%). During extended EEG, the distribution of EDs was as follows: SI, 12/55 (21.8%); SII, 2/43 (4.6%); and SIII 0/41 (0%). The yield, however, did not increase beyond the 13th hour. In undiagnosed episodes of loss of consciousness group (11), yield was 0/11 in all segments.
(1) There was no value added for yield of EDs by extending the EEG recording beyond 13 hours in epilepsy group. (2) The probability of capturing EDs is negligible if the clinical history does not clearly support the diagnosis of seizure or epilepsy.
本研究旨在通过比较记录开始的前30分钟与随后的23.5小时内癫痫样放电（EDs）的出现情况，评估24小时动态脑电图（AEEG）的附加价值。
对分为癫痫组和未确诊的意识丧失发作组的受试者的AEEG进行回顾性研究。AEEG被分为早期脑电图（E-EEG）（前30分钟）和延长脑电图（其余23.5小时）。延长脑电图进一步分为几段（S）：第31分钟至第8小时（SI）、第9至第16小时（SII）和第17至第24小时（SIII）。对每一段连续的脑电图进行检查，以识别先前未发现的新的EDs。
纳入57份AEEG，中位年龄为36.3岁，范围为18.7至78.6岁。有38名（66.6%）女性。AEEG检测EDs的总阳性率为19/57（33.4%）。新EDs的E-EEG阳性率为5/57（9%）。在延长脑电图期间，EDs的分布如下：SI，12/55（21.8%）；SII，2/43（4.6%）；SIII 0/41（0%）。然而，阳性率在第13小时后没有增加。在未确诊的意识丧失发作组（11例）中，所有时间段的阳性率均为0/11。
（1）在癫痫组中，将脑电图记录延长超过13小时对EDs的阳性率没有附加价值。（2）如果临床病史不能明确支持癫痫发作或癫痫的诊断，捕捉到EDs的可能性可以忽略不计。
