Repetitive transcranial magnetic stimulation in drug‐resistant idiopathic epilepsy of dogs: A noninvasive neurostimulation technique

BACKGROUND: Although repetitive transcranial magnetic stimulation (rTMS) has been assessed in epileptic humans, clinical trials in epileptic dogs can provide additional insight. OBJECTIVES: Evaluate the potential antiepileptic effect of rTMS in dogs. ANIMALS: Twelve client‐owned dogs with drug‐resistant idiopathic epilepsy (IE). METHODS: Single‐blinded randomized sham‐controlled clinical trial (dogs allocated to active or sham rTMS) (I) and open‐labeled uncontrolled clinical trial (dogs received active rTMS after sham rTMS) (II). Monthly seizure frequency (MSF), monthly seizure day frequency (MSDF), and number of cluster seizures (CS) were evaluated for a 3‐month pre‐TMS and post‐rTMS period and safety was assessed. The lasting effect period of rTMS was assessed in each dog treated by active stimulation using the MSF ratio (proportion of post‐TMS to pre‐rTMS MSF) and treatment was considered effective if the ratio was <1. RESULTS: No adverse effects were reported. In trial I, MSF and MSDF decreased significantly (P = .04) in the active group (n = 7). In the sham group (n = 5), no significant changes were found (P = .84 and .29, respectively). Cluster seizures did not change significantly in either group. No significant differences were detected between the groups. In trial II, previously sham‐treated dogs (n = 5) received active rTMS and significant decreases in MSF and MSDF were noted (P = .03 and .008, respectively). The overall effect of rTMS lasted for 4 months; thereafter, the MSF ratio was >1. CONCLUSIONS AND CLINICAL IMPORTANCE: Repetitive transcranial magnetic stimulation may be a safe adjunctive treatment option for dogs with drug‐resistant IE, but large‐scale studies are needed to establish firm conclusions.