Dysphagia and drooling of saliva are frequent symptoms in Parkinson's
disease (PD), occurring in one-half and three-quarters of all patients
, respectively, Aspiration related to swallowing is a major cause of m
orbidity and mortality in PD, Defects in oral, pharyngeal, and esophag
eal phases of swallowing have been documented in patients with PD, and
these defects precede symptoms, This paper reviews the current knowle
dge concerning swallowing abnormalities in PD. The pathogenesis of dys
phagia and drooling of saliva is multifactorial, involving cognitive a
nd psychological changes in addition to abnormalities of the extrapyra
midal and autonomic nervous systems, Videofluoroscopic imaging of the
upper esophageal sphincter and pharynx during mastication and swallowi
ng has been the basis of our understanding of the mechanical malfuncti
on present in patients with PD, Manometric abnormalities of the esopha
geal body and lower esophageal sphincter have also been documented, Th
e use of combined manofluoroscopy to examine the upper esophageal sphi
ncter and pharynx in PD offers great promise both in understanding the
defects and directing therapy, Voluntary airway protection techniques
may reduce aspiration, but they need to be tested in a clinical study
, Such maneuvers may reduce the morbidity seen in PD.