EEG latency analysis for hemispheric lateralisation in Landau-Kleffner syndrome

Area of Science:

• Neuroscience
• Epileptology
• Medical Technology

Background:

• Landau-Kleffner syndrome (LKS) is a rare disorder characterized by acquired epileptic aphasia.
• Accurate lateralization of epileptiform discharge origin is crucial for pre-surgical planning in LKS.
• Current methods for lateralization, such as pharmacological tests, may have limitations.

Purpose of the Study:

• To evaluate the reliability of latency analysis for lateralizing epileptiform discharges in LKS.
• To compare latency analysis findings with pharmacological test results.
• To assess the non-invasive potential of latency analysis in LKS pre-surgical assessment.

Main Methods:

• Developed a computer-aided method for identifying leading epileptic discharge regions and measuring inter-hemispheric latencies.
• Analyzed scalp and intracranial EEG recordings from seven LKS patients undergoing surgery.
• Compared laterality indicated by latency analysis with that from pharmacological tests.

Main Results:

• Latency analysis consistently identified a leading hemisphere for bilateral discharges.
• Earliest low-amplitude deflections were consistently localized to temporal regions.
• Latency analysis of earliest low-amplitude deflections accurately predicted the hemisphere in all 7 patients, matching pharmacological tests.
• Latency analysis of later components showed agreement in 6 out of 7 patients.

Conclusions:

• Latency analysis is a reliable, non-invasive method for determining the hemisphere driving bilateral discharges in LKS.
• This technique can confirm, and potentially substitute, findings from pharmacological tests in pre-surgical evaluations.