Peer-reviewed veterinary case report
Monocular ictal nystagmus in a dog: potentially a newly recognized focal seizure phenotype.
- Journal:
- Journal of veterinary internal medicine
- Year:
- 2026
- Authors:
- De Frias, João Miguel et al.
- Affiliation:
- The Royal (Dick) School of Veterinary Studies Hospital for Small Animals · United Kingdom
- Species:
- dog
Plain-English summary
A 3-year-old male neutered toy Chinese crested powderpuff dog suddenly became very dull and then experienced severe seizures. When the veterinarian examined him, they found signs of a problem in the right side of his brain. The dog had unusual eye movements, with one eye moving differently than the other, and imaging tests showed multiple lesions in the brain. Tests of the fluid around the brain indicated inflammation, and brain activity recordings suggested seizures were occurring. Unfortunately, despite treatment, the dog did not survive.
Abstract
A 3-year-old, male neutered toy Chinese crested powderpuff dog was presented with an acute onset obtundation that progressed to status epilepticus. On presentation, neurological examination was localized to a right forebrain lesion. Bizarre episodes, consisting of disconjugate nystagmus of the left eye, medial strabismus of the right eye with convergent-retraction movements in both eyes, were recorded. Head magnetic resonance imaging revealed intra-axial multifocal lesions affecting the right fronto-temporal cortices and dorsal paramedian thalamus. Cerebrospinal fluid analysis revealed a marked mononuclear pleocytosis. Electroencephalographic recordings revealed recurrent medium-amplitude interictal isolated spikes, and suspected epileptic spikes alongside with eye movement that were mainly visible in the right hemisphere. The presumptive diagnosis was meningoencephalitis of unknown origin. Despite treatment, the dog died. This is a report of monocular nystagmus with a presumptive epileptic origin in veterinary medicine, a rare clinical sign in human patients.
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Search related cases →Original publication: https://pubmed.ncbi.nlm.nih.gov/41742548/