CASE 12 — Patient presents with lower facial drooping but the eye is NOT affected. Which muscle is responsible for the drooping?

Correct answer: B. Orbicularis oris

• A. Masseter elevates the mandible for chewing; not responsible for facial drooping.
• B. Lower facial drooping (sagging of the corner of the mouth, lower face asymmetry) WITHOUT eye involvement indicates either peripheral facial nerve palsy limited to lower branches OR a central lesion sparing the forehead. The orbicularis oris and surrounding lower facial muscles are responsible for the observed drooping.
• C. Digastric depresses the mandible/opens the mouth; not associated with facial drooping.
• D. Orbicularis oculi closes the eye. If the eye were affected (unable to close), this would be relevant. The question specifies the eye is UNAFFECTED.