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to fuse with the medial nasal process. The mandibular process (answers
a and b)doesnotnormally fuse with either the lateral or medial nasal
processes (answer c).That would reduce the size of the mouth. The lat-
eral and medial nasal processes (answer e)fuse to form a nostril separate
from the oral cavity.


288.The answer is c.(Moore and Dalley, pp 944, 1141.)Tic douloureux or
trigeminal neuralgia is a sudden pain about one of the branches of the
trigeminal nerve (CN V). It is generally due to vascular compression by cere-
bral arteries on a portion of the trigeminal nerve that causes pain, especially
during situations that cause increases in blood pressure. Ménière’s disease
(answer a)is generally associated with vertigo, nausea, or tinnitus, thought
to be due to failure to maintain proper endolymphatic pressure. Horner’s
syndrome (answer b)is characterized by a ptosis of the upper eyelid, a mio-
sis of the pupil and anhidrosis (reduced sweating), all a result of loss of head
sympathetic innervation. Wry neck (answer d)may be due to tearing of the
sternocleidomastoid muscle during the birthing process. Craniosynostosis
(answer e)is an abnormal head shape often due to the premature replace-
ment of a fibrous cranial suture with bone.


289.The answer is d.(Moore and Dalley, p 1110.)The palatine tonsil sits
in the lateral wall of the oropharynx in the palatine arch posterior to the
palatoglossus muscle and anterior to the palatopharyngeus muscle. The
glossopharyngeal CN (IX) traverses the bed of the pelatine tonsil and car-
ries afferent information to the brain regarding both general sensation and
the special sense of taste from the posterior one-third of the tongue. The
glossopharyngeal nerve is at risk for being cut during tonsillectomy. The
ability to taste in the anterior two-thirds of the tongue (answer a)isnotat
risk because that information is carried by the lingual nerve, below the
tongue. The ability to protrude your tongue (answer b)is provided by
innervation from the hypoglossal nerve, which innervates all the intrinsic
tongue muscles and lies below the tongue and is nota risk. The mandibular
division of the trigeminal CN (V 3 ) does notcourse near the palatine arch
and would notbe at risk. It aids in the opening of the mouth (answer c)
and movement of the mandible from side-to-side(answer e).


290.The answer is d.(Moore and Dalley, pp 1077–1079.)The vertebral
arteries usually arise from the subclavian arteries (not answer a)and


Head and Neck Answers 441
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