VPI is often not diagnosed or diagnosed late because the palate appears normal and the pharynx is not evaluated. When diagnosed after speech has begun, sparse adenoid mass may be a factor. Hypernasality is the primary presenting factor. Deficits are bilateral and characterized by increased muscular tone. Instrumental evaluation is helpful to measure the function of each subsystem and its contribution to the overall speech deficit.
Deficits are bilateral.
Isolated cranial nerve deficits cause unilateral muscular deficits. When the lesion to the Vagus is above the pharyngeal branch, the soft palate and larynx will demonstrate deficits on the same side and the resulting speech will be hypernasal and breathy. A brainstem stroke or tumor may affect more than one cranial nerve. Flaccidity and atrophy are the major characteristics. May be congenital as in Moebius Syndrome.