A 28-year-old man was admitted for evaluation of uncontrolled seizures. Continuous video-electroencephalogram (EEG) was recorded with standard 10-20 electrode placement. In addition, anterior temporal electrodes (T1 and T2) were used. Over the first 24 hours, one subclinical and one nonconvulsive electroclinical seizure were recorded from the left anterior temporal region. The subclinical seizure was detected on longitudinal bipolar montages only with the inclusion of T1 and T2 channels (Figure 1).
Figure 1.
Temporal lobe seizure visualized with anterior temporal electrodes. A, Electroencephalogram (EEG) in standard longitudinal bipolar (“double banana”) montage demonstrates subtle left temporal slowing. B, The addition of anterior temporal electrodes reveals an evolving ictal rhythm at T1, with seizure onset denoted by arrow.
Altered mental status is frequent in the inpatient setting, and electrographic seizures have been reported in approximately 20% of patients undergoing continuous EEG monitoring.1 Visual analysis with a longitudinal bipolar montage remains the mainstay of video-EEG interpretation. American Clinical Neurophysiology Society guidelines suggest the addition of anterior temporal electrodes to facilitate seizure detection over the underlying temporal regions.2 However, longitudinal bipolar anterior temporal montages are likely underutilized in standard EEG interpretation. Use of these montages can improve visual detection of subtle temporal seizures with minimal technical or clinical burden,3 and therefore may lead to more rapid seizure treatment and improvement in neurologic outcomes.4
Footnotes
Authors’ Note: Souzana Obretenova contributed to case concept and design, acquisition of data, interpretation of data, manuscript writing, figure editing, and literature review. Mauricio F. Villamar contributed to case concept and design, acquisition of data, interpretation of data, manuscript editing, figure editing, and literature review. Steven Tobochnik contributed to case concept and design, acquisition of data, interpretation of data, manuscript editing, figure generation, and clinical care. Mauricio F. Villamar is also affiliated with the Department of Neurology, Warren Alpert Medical School of Brown University, Providence, RI, USA and Steven Tobochnik is also affiliated with VA Boston Healthcare System, Jamaica Plain, MA, USA
Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article.
ORCID iD: Souzana Obretenova, MD 
https://orcid.org/0000-0002-2239-3146
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