Abstracts

Rationale: Long Term Monitoring (LTM) is a valid diagnostic tool to evaluate epileptic patients for seizure activity and for assessment of treatment during clinical and subclinical Status Epilepticus (SE) (1-4). Canine epilepsy represents the most common neurological disease (>5%) in veterinary medicine. Epileptic dogs are commonly affected by generalized and focal seizures. The clinical symptomatology of focal seizures is variable and in many occasions it is difficult to differentiate non-epileptic activity from focal epileptic activity based on clinical semiology and history (5). A canine epilepsy monitoring unit (canine EMU) was recently set up in our ICU to monitor epileptic dogs for seizure activity and long-term management of cases refractory to conventional antiepileptic drugs. Methods: Two clinical cases are presented to demonstrate practical applications of LTM in canine epilepsy. Results: Case 1 “Mojo” is a 3 yo male Chihuahua that was referred to the VTH-OVC neurology service for continuous episodes of head and nose twitching. “Mojo” was admitted to the canine EMU for LTM. A standard electrode placement using 13 subdermal wire electrodes including reference and ground was adopted (6). The recording electrodes were secured in place with a proper bandage to avoid movements and disconnection. The recording lasted 8 hours during which “Mojo” experienced multiple episodes of head and nose twitching that were electroencephalographically characterized by generalized 4Hz spike and wave activity (Fig.1). A brain MRI was performed and no structural abnormalities were noted. Based on these findings, a diagnosis of idiopathic epilepsy was made and treatment with Phenobarbital was started. Case 2 “Levi” is a 2 yo male French Bulldog that was presented with focal SE characterized by extreme confusion, foaming, compulsive circling and facial twitching. “Levi” was previously diagnosed with idiopathic generalized epilepsy and he was treated with Phenobarbital, Potassium bromide, and Levetiracetam. Upon presentation, “Levi” was admitted to the canine EMU for LTM and management of focal SE. Constant polyphasic waves and spike and wave activity were recorded bilaterally and symmetrically. Treatment with diazepam was started along with repetitive intravenous boluses of Phenobarbital. Since no significant improvement was noted, Propofol constant rate infusion (CRI) was initiated to suppress bursts of pathological cortical electrical activity (Fig.2). Drug dosages were adjusted in accordance to the video-EEG findings that were simultaneously recorded. Despite aggressive treatment with AEDs, pathological cortical electrical activity continued to subsist indicating a poor prognostic factor. Conclusions: LTM performed in an appositely designed canine EMU can facilitate the investigation of different aspects of phenomenology of canine seizures including the determination of a seizure versus non-epileptic activity and the source of epileptic activity (“seizure focus”). In refractory epileptic patients or dogs presented with SE, LTM is essential to monitor subject’s response to treatment with different AEDs and to establish a prognosis of successful outcome.