Electrophysiologic patterns of oral-pharyngeal swallowing in parkinsonian syndromes.
OBJECTIVE
To assess the presence, severity, and differences in dysphagia in Parkinson disease (PD), Parkinson variant of multiple system atrophy (MSA-P), and progressive supranuclear palsy (PSP), and to study the pathophysiology of swallowing abnormalities in these disorders.


METHODS
We applied an electrophysiologic method to evaluate oral-pharyngeal swallowing. We analyzed the following measures: duration of EMG activity of suprahyoid/submental muscles (SHEMG-D); duration of laryngeal-pharyngeal mechanogram (LPM-D); duration of the inhibition of the cricopharyngeal muscle activity (CPEMG-ID); interval between onset of EMG activity of suprahyoid/submental muscles and onset of laryngeal-pharyngeal mechanogram (I-SHEMG-LPM); and swallowing reaction time (SRT).


RESULTS
The prolongation of I-SHEMG-LPM was more typical in PD, whereas the most distinctive finding both in patients with PSP and MSA-P was the reduction or the absence of CPEMG-ID early in the course of the disease.


CONCLUSIONS
Involvement of the peduncolo-pontine tegmental nucleus, with subsequent dysfunction of basal ganglia and of the medullary central pattern generator of swallowing, may account for the abnormalities detected in these parkinsonian syndromes. The method described was able to identify swallowing abnormalities also in patients without symptoms of dysphagia and to evaluate dysphagia severity in all patients.
Alfonsi
E
E
Spinal and Cranial Reflexes Laboratory, Department of Neurological Sciences, Università di Pavia, Pavia, Italy. enrico.alfonsi@mondino.it
Versino
M
M
Merlo
I M
IM
Pacchetti
C
C
Martignoni
E
E
Bertino
G
G
Moglia
A
A
Tassorelli
C
C
Nappi
G
G
D000368:Aged; D000369:Aged, 80 and over; D003679:Deglutition; D003680:Deglutition Disorders / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D004576:Electromyography; D005260:Female; D006801:Humans; D007821:Laryngeal Muscles / Q000294:innervation / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D019578:Multiple System Atrophy / Q000150:complications / Q000503:physiopathology; D009119:Muscle Contraction / Q000502:physiology; D010300:Parkinson Disease / Q000150:complications / Q000503:physiopathology; D020734:Parkinsonian Disorders / Q000150:complications* / Q000503:physiopathology*; D010614:Pharynx / Q000294:innervation / Q000503:physiopathology*; D011237:Predictive Value of Tests; D011930:Reaction Time; D013494:Supranuclear Palsy, Progressive / Q000150:complications / Q000503:physiopathology; D014059:Tongue / Q000294:innervation / Q000503:physiopathology