Electroencephalography Findings in Healthy and Finnish Spitz Dogs with Epilepsy: Visual and Background Quantitative Analysis

Abstract

Background: Qualitative and quantitative electroencephalography (EEG) parameters of healthy and Finnish Spitz dogs with epilepsy have not been determined.Objective: To determine if EEG can provide specific characteristics to distinguish between healthy dogs and dogs with epilepsy.Animals: Sixteen healthy and 15 Finnish Spitz dogs with epilepsy. Methods: A prospective clinical EEG study performed under medetomidine sedation. Blinded visual and quantitative EEG analyses were performed and results were compared between study groups.Results: Benign epileptiform transients of sleep and sleep spindles were a frequent finding in a majority of animals from both groups. The EEG analysis detected epileptiform activity in 3 Finnish Spitz dogs with epilepsy and in 1 healthy Finnish Spitz dog. Epileptiform activity was characterized by spikes, polyspikes, and spike slow wave complexes in posterior-occipital derivation in dogs with epilepsy and with midline spikes in control dog. The healthy dogs showed significantly less theta and beta activity than did the dogs with epilepsy (P , .01), but the only significant difference between healthy dogs and dogs with untreated epilepsy was in the alpha band (P , .001). Phenobarbital treatment increased alpha, beta (P , .001), and theta (P , .01), and decreased delta (P , .001) frequency bands compared with dogs with untreated epilepsy.Conclusions and Clinical Importance: Benign epileptiform transients of sleep could be easily misinterpreted as epileptiform activity. Epileptiform activity in Finnish Spitz dogs with epilepsy seems to originate from a posterior-occipital location. The EEG of dogs with epilepsy exhibited a significant difference in background frequency bands compared with the control dogs. Phenobarbital treatment markedly influenced all background activity bands. Quantitative EEG analysis, in addition to visual analysis, seems to be a useful tool in the examination of patients with epilepsy.

Activation procedures in the electroencephalograms of healthy and epileptic cats under propofol anaesthesia

“…The occurrence of paroxysmal discharges in the EEGs of epileptic dogs varies among laboratories between 20 and 86 per cent (Holliday and others 1970, Jaggy and Bernadini 1998, Berendt and others 1999, Jeserevics and others 2007). In the current study, 54 per cent of all investigated cats did not show any abnormal activity in their EEGs although they had a history of generalised seizures as described by the owners.…”

Electroencephalography recording analysis in monitoring of canine idiopathic epilepsy treated with phenobarbital. Pilot study

“…During the visual analysis eplieptiform findings such as: sharp waves, slow waves and focal spikes were noticed. The patients also showed findings unrelated to epilepsy: sleep spindles and K-complexes (Jeserevics et al 2007). In 10 dogs (71%) high amplitude (20-90 μV and low frequency 1-2.5Hz EEG background activity were presented and 4 dogs (29%) presented low amplitude (4-15 μV) and high frequency EEG background activity.…”

“…The alpha and beta activity also increased compared to EEG before phenobarbital treatment, but the results were not statistically significant. Jeserevics et al (2007) in their study conducted on Finnish Spitz with epilepsy noticed that phenobarbital treatment increased alpha, beta and theta bands and decreased the delta band compared to untreated dogs. In 12 dogs (85.71%) fewer seizure episodes were observed.…”

Absence Seizures as a Feature of Juvenile Myoclonic Epilepsy in Rhodesian Ridgeback Dogs

“…Moreover, a definitive diagnosis of absence seizures requires confirmation by EEG. In the majority of studies in which EEG was used as a diagnostic tool, dogs were sedated or even anesthetized . This technique makes the diagnosis of absence seizures challenging, because level of alertness or consciousness, a key factor for the diagnosis of absence seizures, cannot be assessed.…”