Gross Anatomy USMLE Step 1 Practice Question
A 61-year-old female undergoes surgery to remove a solitary painless mass just anterior to the tragus of her left ear. Pathologic examination shows a well-circumscribed, yellowish-white tumor with a proliferation of epithelial and myoepithelial cells in duct formations within a background of loose myxoid tissue. During the surgery, particular attention is paid to the nerve that exits the skull via the stylomastoid foramen, passes lateral to the styloid process, and then enters this affected structure. Injury to the lower division of this nerve during surgery will most likely result in which of the following?
Answer choices
- ANumbness over the angle and mental region of the jaw on the same side
- BInability to furrow the brow (to frown) on the same side
- CPtosis of the eye on the same side
- DWeakness of the lower lip on the same sideCorrect answer
- EWeakness in closing the eye on the same side
- FInability to elevate the corner of the mouth on the same side
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