second branchial arch) and raises that bone during swallowing. The distal
tendon of the stylohyoid muscle is split by the digastric muscle (not
answer d) passing through its trochlea attached to the lesser horn. The
styloglossus muscle acts to retract the tongue (answer b). The spheno-
mandibular ligament inserts onto the lingula of the mandibular foramen
(answer c);the stylohyoid ligament inserts onto the lesser horn of the
hyoid bone. The stylopharyngeus muscle inserts of the into the middle
pharyngeal constrictor.
306.The answer is c.(Moore and Dalley, p 1019.)He suffers from sinusi-
tis, which has eroded through the wall on the frontal sinus, and since the
frontalis muscle is notattached to bone, allows pus to leak into the upper
eyelid. Inflammation of the mucous membrane that lines the sinuses may
sometimes lead to a build up of pus that can block the normal drainage
pathways. If pressure builds, erosion of the bony wall of the sinus can occur.
In this instance, the anterior wall of the frontal sinus was compromised and
pus escaped into the forehead and into the upper eyelid, since the frontalis
muscle, a normal barrier, attaches only into skin of the forehead. In order to
allow movement, the skin of the eyelid is only attached to underlying struc-
tures by loose areolar connective tissue, through which infections easily
spread. Intravenous antibiotics were initiated. The swelling spontaneously
reduced after the first week of treatment and no visible defects were noted
1 month later. Trigeminal neuralgia or tic douloureux (answers a and b)is
characterized by sudden sharp pains over the distribution of one or more
branches of the trigeminal nerve. Although pain is perceived within the
ophthalmic division, the teenager would notsuffer from sudden sharp
twinges of pain, rather a dull constant pain from swollen tissue. Bell’s
palsy(answer d)is generally caused by a herpes simplex virus infection
of the facial nerve within the facial canal that causes unilateral facial paral-
ysis, which would limit one’s ability to close the upper eyelid, notraise it.
A sty (answer e)is an inflammation of the sebaceous gland, associated
with each eyelash or cilia. A chalazion is an inflammation of a Meibomian
or tarsal gland, which lies on the inner surface of the eyelid. This could
cause a bulge in the upper eyelid but does notfit with the other clinical
findings.
307.The answer is d.(Sandler, p 294.)In the family of conditions known
as spina bifida, failure of the dural portions of the developing vertebrae may
448 Anatomy, Histology, and Cell Biology