Canine Electroencephalography Electrode Positioning Using a Neuronavigation System.

Simple Summary: Simple Summary: This study investigated the current methods of placing electrodes used to measure the electrical activity of the brain in dogs. Recording the brain's electrical activity can be of great importance, for example, in dogs affected by epilepsy. Electrodes are placed manually, by orienting oneself on landmarks of the skull. This study investigated this positioning using a 3D cranial navigation system and found that manual electrode placement leads to a high variance in electrode positions. Unprecise electrode positions could influence the recording quality of the brain's electrical activity, as different electrode positions also record different areas of the brain. A cranial navigation system can be used to place electrodes precisely. This can be of importance when using recordings in research settings, when recordings of particular areas of the brain are required, or when the electrical activity of the same individual is recorded in repeated sessions and these recordings should be comparable. Background: Studies in people suggest that surface electroencephalography (EEG) electrode positions vary across participants and that the consistency of these positions is electrode-, region-, and examiner-dependent. The aim was to investigate the variability in EEG electrode positions to their underlying cortical regions (CRs) in dogs using a neuronavigation system and evaluate the use of said system in electrode positioning, via a cadaver study with 22 dogs. CT scans and MRI were performed for each dog. These were uploaded onto a neuronavigation system where the desired CRs were annotated. The electrode positions were marked on the heads, which were positioned using only a previously established guide and anatomical landmarks. Using the neuronavigation system, alignment or deviations from the desired CRs were noted. Fifty-three percent of all the marked electrode positions showed an alignment with the desired CRs. Thirty-three percent showed no alignment, and fourteen percent showed partial alignment. Three percent deviated to different cortical lobes. Placement via the neuronavigation system enabled reliable and replicable electrode positioning and CR alignment. The standard for EEG electrode placement in dogs is subjected to a high variance. A neuronavigation system can aid in more precise electrode placements. Specific gyri cannot accurately be evaluated on EEG without imaging-controlled electrode placement. [ABSTRACT FROM AUTHOR]