Clinical, Electroencephalographic and Neuroimage Findings of Patients with Cerebellar Ataxia and Epilepsy
Emanuel Cassou1, Luciano De Paola1, Salmo Raskin2, Paula Marques3, Quratulain Zulfiqar Ali4, Farah Qaiser3, Danielle Andrade3, Helio Afonso Teive1
1Clinical Hospital of the Federal University of Parana, 2Genetika Laboratory, 3University of Toronto, 4Toronto Western Hospital
Objective:
To describe phenotypical, imaging and neurophysiological features of patients affected by cerebellar ataxia and epilepsy.
Background:
The association of epilepsy with hereditary cerebellar ataxia is an emerging issue that has raised interest among researchers in the fields of movement disorders, epilepsy and neurogenetics, particularly the characterization of clinical and neurophysiological findings of affected patients. Although there are thorough descriptions of clinical and electroencephalographic findings of some diseases (such as SCA10 and progressive myoclonic epilepsies), there are no studies that accomplish a systematic correlation of clinical features, EEG and neuroimaging findings as a group of diseases.
Design/Methods:
30 patients from southern Brazil diagnosed with both cerebellar ataxia and epilepsy were retrospectively assessed regarding specific diagnosis, clinical characteristics (severity, disease duration, seizure type and frequency), EEG and neuroimaging findings. Patients were also divided in 3 groups: autosomal dominant ataxias (SCAs), recessive ataxias and progressive myoclonic epilepsies and the findings were compared between those groups.
Results:
The most common diagnosis in each group was SCA10, undefined recessive ataxia and Unverricht Lundborg disease, respectively. A higher severity of ataxia symptoms (SARA rating scale) and worse seizure frequency control was found in patients with progressive myoclonic epilepsies. In 62%, seizure onset was determined to be generalized, with a higher frequency of tonic-clonic seizures. EEG analysis showed higher prevalence of epileptiform activity in the recessive ataxia group (57%, p<0.005). 80% of patients presented cerebellar atrophy on brain MRI, being the isolated abnormal finding in 56%.
Conclusions:
The heterogeneity of the diseases that present cerebellar ataxia and epilepsy can be challenging. Higher frequency of SCA 10 was expected in the AD group, although in the southern Brazilian cohort this is the exception. PME ataxia was more severe and seizure control was poorer, compared to other groups. The results highlight the need for better characterization of epileptic ataxic patients and syndromes.