EEG findings in early-stage corticobasal degeneration and progressive supranuclear palsy: a retrospective study and literature review.
OBJECTIVE
Although neuroimaging and electrophysiological tests are potentially useful to distinguish corticobasal degeneration (CBD) from progressive supranuclear palsy (PSP), little is known about the diagnostic value of electroencephalography (EEG) for their distinction. We assessed the value of EEG for differentiating CBD from PSP.


METHODS
We reviewed conventional EEGs recorded at an early stage of disease in 10 CBD patients and 14 PSP patients. We focused on slowing of background activity (SBA), frontal intermittent rhythmic delta activity (FIRDA) and focal slow waves (FSWs). Statistical analysis was performed by Fisher's exact test.


RESULTS
SBA was observed in 1 CBD patient and 2 PSP patients. FSWs were found in 8 CBD patients (80.0%), but only 2 PSP patients (14.3%) (p=0.002); they appeared contralateral to the dominantly-affected side in 6 of 8 CBD patients, and ipsilateral to the side with most atrophy on MRI in 7 of 8 CBD patients. FIRDA was observed in 2 CBD patients (20.0%) and 5 PSP patients (35.7%) (p=0.357).


CONCLUSIONS
FSWs are characteristic of CBD, but FIRDA was not disease-specific.


CONCLUSIONS
FSWs on EEG, in addition to clinical criteria, yield useful supplementary information to distinguish between these diseases at early stages.
Tashiro
Kenshi
K
Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-Ku, Fukuoka 812-8582, Japan. ketashi@neurophy.med.kyushu-u.jp
Ogata
Katsuya
K
Goto
Yoshinobu
Y
Taniwaki
Takayuki
T
Okayama
Akira
A
Kira
Jun-Ichi
J
Tobimatsu
Shozo
S
D000328:Adult; D000368:Aged; D001480:Basal Ganglia Diseases / Q000175:diagnosis* / Q000503:physiopathology*; D001921:Brain / Q000473:pathology / Q000503:physiopathology; D003937:Diagnosis, Differential; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D013494:Supranuclear Palsy, Progressive / Q000175:diagnosis* / Q000503:physiopathology*