A patient with a base of skull fracture through the cribriform plate of the ethmoid bone presents with CSF rhinorrhea and bilateral periorbital bruising. Loss of which sense is most specific for cribriform plate injury?
- A Taste
- B Vision
- C Smell (anosmia) ✓
- D Hearing
Correct answer: C. Smell (anosmia)
Explanation
The olfactory nerve (CN I) filaments pass through the foramina of the cribriform plate of the ethmoid bone. Fracture across the cribriform plate shears these delicate filaments, causing anosmia — loss of smell. CSF rhinorrhea occurs because the dura and arachnoid are torn and CSF leaks into the nasal cavity via the olfactory foramina. Bilateral periorbital bruising ('raccoon eyes') indicates anterior cranial fossa fracture. Vision loss would implicate the optic canal; hearing loss would indicate petrous temporal bone fracture.
Reference: BD Chaurasia's Human Anatomy, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.