Otic ganglion
Ganglion · CN IX Lesser petrosal Foramen ovale
Sits just below the foramen ovale on the medial side of the mandibular nerve. Receives the lesser petrosal nerve (CN IX) and hands its postganglionic fibres to the auriculotemporal nerve for the parotid gland — the only head ganglion fed by the glossopharyngeal nerve.
Traced from the start
Detail
- Preganglionic route
- Inferior salivatory nucleus → CN IX → tympanic nerve (Jacobson) → tympanic plexus on the promontory → lesser petrosal nerve → foramen ovale → otic ganglion
- Postganglionic distribution
- Auriculotemporal nerve (V3) → parotid gland
- Neighbours
- Lies between V3 and tensor veli palatini; the nerve to medial pterygoid passes through it
When it goes wrong
Parotidectomy severs auriculotemporal parasympathetic fibres, which regenerate into sweat glands and vessels of the overlying skin (both cholinergic)
Frey syndrome: gustatory sweating and flushing of the cheek while eating, months after surgery
Practise this structure
4 questions in the bank tagged Cranial Nerves.
A 52-year-old woman has had two months of numbness over the right forehead, the right upper eyelid and the tip of her nose, with a gritty feeling in the right e…
Foundations · middle twist
A 44-year-old man has had 18 months of worsening hearing on the left with constant ringing in that ear. He still follows conversation in a quiet room but cannot…
Foundations · middle twist
A 58-year-old man has sudden vertigo and a hoarse voice, and chokes when he drinks. The palate elevates to the right and there is no gag response when the left…
Foundations · middle twist
A 27-year-old man was struck on the head at football a week ago. He now sees two images, one above the other, worst when reading or going down stairs. The verti…
Foundations · middle twist