title: Multimodal evoked potentials in multiple system and late onset cerebellar atrophies.
abstract: Forty subjects were clinically examined using scales for cerebellar, pyramidal, parkinsonian, and mental status and by quantitative evaluation of neuroimages. The patients were classified into two groups: cerebellar-plus and "pure" cerebellar syndromes. Patients with "pure" cerebellar syndrome were diagnosed as autosomal dominant cerebellar ataxia III (ADCA III) or "pure idiopathic" late-onset cerebellar ataxia (ILOCA) in this series. Patients with cerebellar-plus syndrome were diagnosed as multiple system atrophy (MSA), subclassified as either ILOCA-plus, ADCA I, ADCA II or autosomal recessive LOCA. We have used visual (VEP), brainstem auditory (BAEP) and somatosensory (SEP) evoked potentials in order to establish their diagnostic validity. Cerebellar-plus syndrome and "pure" cerebellar syndrome showed overlapping VEP, BAEP and SEP abnormalities. VEP P100 latency, however, shows a certain ability to differentiate between the two groups (p = 0.08) and appears useful in distinguishing between sporadic cerebellar-plus syndromes (MSA or ILOCA-plus) and "pure" cerebellar syndromes (p < 0.02). The incidence of prolonged N9-N13 latency was significantly higher in the latter subgroup (p < 0.04) as well. Within cerebellar-plus syndromes, VEP, BAEP and SEP abnormalities were more frequent in inherited cases (ADCA I and II, along with autosomal recessive LOCA) than in sporadic ones. The most apparent differences were a higher incidence of abnormal BAEPs at brainstem level (p < 0.002), and of both peripheral and possible central SEP impairment in hereditary cerebellar-plus syndrome than in sporadic cerebellar-plus syndrome (p < 0.03). EP investigation is useful to a certain extent in differentiating between some variants of LOCA.
authors.affiliation: Servicio de Neurología, Hospital La Paz, Madrid.
authors.forename: J
authors.initials: J
authors.lastname: Arpa
authors.forename: R
authors.initials: R
authors.lastname: López-Pajares
authors.forename: A
authors.initials: A
authors.lastname: Cruz-Martínez
authors.forename: F
authors.initials: F
authors.lastname: Palomo
authors.forename: T
authors.initials: T
authors.lastname: Ferrer
authors.forename: A B
authors.initials: AB
authors.lastname: Caminero
authors.forename: A
authors.initials: A
authors.lastname: Rodríguez-Albariño
authors.forename: M
authors.initials: M
authors.lastname: Alonso
authors.forename: T
authors.initials: T
authors.lastname: Lacasa
authors.forename: J
authors.initials: J
authors.lastname: Nos
mesh_terms: D000328:Adult; D017668:Age of Onset; D000368:Aged; D002524:Cerebellar Ataxia / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology*; D002531:Cerebellum / Q000503:physiopathology*; D003342:Corpus Striatum / Q000503:physiopathology; D016057:Evoked Potentials, Auditory, Brain Stem; D005073:Evoked Potentials, Somatosensory; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index