Rhythmic EEG patterns: The oldest idea in the EEG world, but without an obvious definition

Area of Science:

• Neuroscience
• Clinical Neurophysiology
• Epileptology

Background:

• The term "rhythmic" in electroencephalography (EEG) lacks a precise, universally accepted definition.
• The International Federation of Clinical Neurophysiology's 2017 definition of rhythmic patterns is ambiguous, equating to periodic functions.
• This ambiguity limits the accurate description of various EEG patterns, particularly epileptic seizures and status epilepticus.

Purpose of the Study:

• To analyze the limitations of the current definition of "rhythmic" in EEG.
• To propose a refined, more dynamic definition of rhythmic EEG patterns.
• To improve the accurate identification and interpretation of EEG patterns in critically ill patients.

Main Methods:

• Review of the current definition of rhythmic EEG patterns.
• Analysis of the applicability of the definition to physiological and pathological EEG waveforms.
• Proposal of a dynamic approach incorporating spatiotemporal evolution for a broader definition.

Main Results:

• The existing definition of rhythmic EEG patterns is too narrow, primarily describing periodic functions.
• This definition inadequately covers most epileptic seizures and status epilepticus.
• A dynamic approach, considering waveform evolution, is necessary for a comprehensive understanding.

Conclusions:

• The current definition of "rhythmic" in EEG requires revision to include dynamic characteristics.
• Distinguishing between periodic and rhythmic EEG features is critical for accurate patient diagnosis.
• A more inclusive definition will enhance the interpretation of EEG in critical care settings.