OTIC GANGLION

 OTIC GANGLION

INTRODUCTION:-

     It is a small peripheral parasympathetic ganglion which relays secretomotor fibers to the parotid gland. 

     Topographically, it is intimately related to the mandibular nerve but functionally it is related to glossopharyngeal nerve. 

SIZE:-

     Pinhead [ 2-3 mm in size ]

SHAPE:-

     Oval in shape. 

LOCATION:- 

     Infratemporal fossa, just below the foramen ovale. 

RELATIONS:- 

Lateral:- 

Mandibular nerve

Medial:-

Tensor palati muscle

Posterior:-

Middle meningeal artery

Anterior:-

Medial pterygoid muscle

ROOTS (OR) CONNECTIONS:-

     1. Parasympathetic root ( secretomotor) 

     2. Sympathetic root

     3. Sensory 

     4. Somatic motor

1. Parasympathetic root ( secretomotor) :-

     - Form lesser petrosal nerve. 

2. Sympathetic root:-

     - From sympathetic plexus around the middle meningeal artery. 

     Preganglionic sympathetic fibres arises from T1 and T2 spinal segment, then relay in the superior cervical sympathetic ganglion. 

     Postganglionic fibres arises in the superior cervical ganglion. The fibres pass through the otic ganglion without relay and reach the parotid gland via the auriculotemporal nerve. 

     They are vasomotor in function. 

     Responsible for thick salivary secretion. 

3. SENSORY:-

     From auriculotemporal nerve and is sensory to the parotid gland. 

4. SOMATIC MOTOR:- 

     Nerve to medial pterygoid. It passes through ganglion to supply medial pterygoid, tensor palati and tensor tympani muscles. 

BRANCHES:-

     Postganglionic parasympathetic, postganglionic sympathetic, sensory are all supply parotid gland through auriculotemporal nerve. 

     Fibres from nerve to medial pterygoid pass through otic ganglion without relay and supply tensor palatini and tensor tympani. 

     Otic ganglion connected to chorda tympani and nerve of pterygoid canal alternate route of taste pathway. 

CLINICAL SIGNIFICANCE:-

Frey's syndrome:-

- Due to damage of auriculotemporal nerve. 

- Salivation induce perspiration ( sweating). 

- Accompanied with ERYTHEMA ( reddening of skin).