A patient with a cavernous sinus thrombosis loses the afferent limb of the corneal blink reflex bilaterally. Which nerve carries the corneal sensory fibres that were interrupted?
- A Short ciliary nerves
- B Lacrimal nerve
- C Nasociliary nerve ✓
- D Frontal nerve
Correct answer: C. Nasociliary nerve
Explanation
Corneal sensation travels through the long ciliary nerves to the nasociliary nerve, a branch of the ophthalmic division (V1) of the trigeminal nerve, then via the trigeminal ganglion to the main sensory nucleus. The efferent limb of the blink reflex is the facial nerve to orbicularis oculi. The short ciliary nerves carry postganglionic parasympathetic and sympathetic fibres, not corneal somatosensory fibres, and the frontal and lacrimal nerves do not supply the cornea.
Reference: Snell's Clinical Neuroanatomy, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.