All are TRUE about Frey syndrome EXCEPT
A. Gustatory sweating
B. Aberrant reinnervation of preganglionic parasympathetic neurons to nearby denervated sweat glands
C. Postoperative phenomenon commonly found following salivary gland surgery
D. Confirmed by ‘Minor test’
Gustatory sweating and flushing
Frey syndrome is a postoperative phenomenon
Most Commonlly found – following salivary gland surgery.
Less commonly seen after neck dissection, facelift procedures, and trauma.
Characterized by gustatory sweating and flushing.
Synkinetic mechanism for Frey syndrome
Aberrant reinnervation of postganglionic parasympathetic neurons to nearby denervated sweat glands and cutaneous blood vessels.
Results in – flushing and sweating in the sympathetically void skin in response to mastication and salivation.
The previous sympathetic responses of sweating and flushing are now controlled by postganglionic parasympathetic fibers.
Mastication, which releases acetylcholine from the parasympathetic nerve endings, now induces sweating and flushing, which was a sympathetic cholinergic response before synkinesis of parasympathetic nerve fibers.
Changes in normal innervation of the parotid gland
Normal innervation of the parotid gland by the postganglionic parasympathetic nerve fibers from the auriculotemporal nerve.
Postoperative state -the regenerated postganglionic parasympathetic nerve fibers extend to the overlying cutaneous tissue.
Postganglionic parasympathetic nerve fibers innervating the cutaneous sweat gland that results in gustatory sweating.
Minor starch-iodine test
- Painting the patient’s postsurgical affected region with iodine.
- Once dry, dry starch is then applied to the painted area
- Salivary stimulus is given.
- The starch turns blue/brown in the presence of iodine and sweat.