Facial Nerve
Forceps or pressure injury to the facial nerve at birth is the usual cause of complete one-sided facial weakness in an infant.
What our notes say
- Forceps or pressure injury to the facial nerve at birth is the usual cause of complete one-sided facial weakness in an infant. (Paediatrics end of fourth year special supplementary exam: August 2019, Paper On)
- Symptoms: Foul-smelling otorrhea, conductive hearing loss, earache, vertigo, facial nerve palsy. (Head &neck sem 2 — Past Paper Questions & Answers)
- Complications: Cholesteatoma can erode ossicles, the facial nerve canal, or the skull base (serious complications like meningitis); Otosclerosis mainly limited to stapes fixation, rarely causes serious extracranial complications (Head & Neck Pathology MCQs: Oral, Ear, Throat & Gland Tumors)
- Facial nerve palsy — UMN vs LMN (*3, frequently tested): (Cranial Nerves, Eye Exam & Vital Signs: MBChB Clinical Revision)
- Reactivation in geniculate ganglion of facial nerve (CN VII) (EXAM: Basic Virology, Viral Replication, Prions & Slow Viruses, Poxviruses & VZV)
- Triad: painful vesicles in ear canal and pinna + ipsilateral facial nerve palsy + hearing loss/tinnitus/vertigo (EXAM: Basic Virology, Viral Replication, Prions & Slow Viruses, Poxviruses & VZV)
Study material on Facial Nerve
Practice questions on Facial Nerve
A patient with facial nerve palsy, meningitis, and rash has CSF showing gram-negative diplococci. The organism is
- Streptococcus pneumoniae
- Haemophilus influenzae
- Neisseria meningitidis
- Neisseria gonorrhoeae
- The organism appears as gram-negative kidney bean-shaped diplococci in CSF.
Answer: E. N. meningitidis causes meningococcemia with petechial/purpuric rash, meningitis, and can affect cranial nerves including the facial nerve. The organism appears as gram-negative kidney bean-shaped diplococci in CSF. ---
A patient with facial nerve palsy, meningitis, and rash has CSF showing gram-negative diplococci. The organism is
- Streptococcus pneumoniae
- Haemophilus influenzae
- N. meningitidis
- Neisseria gonorrhoeae
- Occurs only after chronic exposure
Answer: C. N. meningitidis causes meningitis with petechial rash and appears as gram-negative kidney bean-shaped diplococci. ---
A patient sustained a penetrating injury to the cheek, resulting in an inability to raise the corner of the mouth when smiling. Which branch of the facial nerve was most likely damaged?
- Temporal branch
- Zygomatic branch
- Buccal branch
- Marginal mandibular branch
Answer: B. The zygomatic branch of the facial nerve (CN VII) innervates the orbicularis oculi and muscles that raise the upper lip and corner of the mouth (e.g., zygomaticus major and minor), which are essential for smiling.