PAROTID GLAND Dr Shivarama Bhat Curtsey Slideshare Salivary

PAROTID GLAND Dr Shivarama Bhat Curtsey: Slideshare

Salivary Glands : 3 paired – Parotid Submandibular Sublingual Scattered - Tongue Palate Cheeks Lips Function : Chewing Swallowing Saliva (Digestion by Enzymes) Serous & Mucinous

GUT TUBE Stomodeum Buccopharyngeal membrane Pre-Laryngeal (Cephalic part) Fore-gut Post-Laryngeal (Caudal part) Mid-gut Hind-gut Proctodeum Cloacal membrane Pharynx and Part of definitive Mouth cavity Skin ectoderm Ectodermal furrow Parotid gland 4 th week of IUL

The salivary glands arise as buds from The epithelial lining of the mouth; the parotid appears during the fourth week In the angle between the maxillary process and the mandibular arch Opening of parotid duct indicates position of angle of primitive mouth

Parotid region Ext. acoustic meatus Sternomastoid Ramus of mandible

Parotid gland: Largest saliv. Gland Wt. 15 gms Serous secretion Capsule – True – condensation of fibrous stroma of gland False - investing deep fascia Superficial thick – adherent to gland Deep – thin – attached to styloid process forms – stylomandibular Lig. (separates parotid from submandibular sal. gland.

Parotid region Ext. acoustic meatus Sternomastoid Ramus of mandible

Parotid – 3 sided pyramid Medial border l ia ed m o- e er ac st urf s Po ial d e m e o er rfac t An su Superior surface (Base) Superficial surface Anterior border Posterior border Apex

Presenting parts 01. Apex 02. Base 03. Superficial (lateral) surface 04. Antero-medial surface 05. Postero-medial surface

1. Apex Overlaps post. Belly of digastric appears in carotid triangle, related to stylomandibular ligament Structures passing thro’ 01. Cervical branch of facial nerve 02. Ant. division of retro-mandibular vein 03. Formation of ext. jug. vein

2. Base Concave related to; Ext. acoustic meatus Post. Part of TM joint Structures passing thro’ 01. Temp. br. Of facial nerve 02. Sup. Temp. vessels 03. Auriculo-temp. nerve

3. Antero-medial surface Deeply grooved by ramus of mandible; Relations: 01. Post. Inf. Part of masseter 02. Post. Border of ramus of mandible 03. Med. Pterygoid muscle insertion 04. Outer lip – branches of facial nerve 05. Inner lip - Maxillary art. Medial to neck of mandible 05 03 05 01 02

3. Postero - medial surface Extensive Relations: • Mastoid process with Sternomastoid Post. Belly of digastric 02. Styloid process with muscles 03. Transverse process of atlas and Rectus capitis lateralis 04. Deep to styloid – Int. carotid - Int. Jug. Vein in between 9, 10, 11, 12 cr. nerves 05. Facial nerve after emerging from SM foramen pierces the gland 06. Ext. carotid first lodges in groove then pierces the gland

1. Anterior border From above downwards: 01. Zygomatic br. of facial nerve 02. Transverse facial vessels 03. Upper buccal br. of facial nerve 04. Acc. Parotid gland & duct if present 05. Parotid duct 06. Lower buccal br. of facial nerve 07. Marginal mandibular br. of facial nerve 2. Posterior border Rests on masseter 01. Post. Auricular br of facial nerve 02. Post. Auricular vessels

Parotid duct (stensen’s duct) 5 cms long, starts at mid point of ant. Border Runs on masseter, opens opp. crown of upper 2 nd Molar Sup: Upper buccal br. of facial, Transverse facial vessels. Inf: Lower buccal br. of facial Pierces: 1. Buccal pad of fat, 2. Buccopharyngeal fascia 3. Buccinator

Parotid duct Surface marking

Processes of the parotid gland: 01. Facial process - Superficial to masseter along parotid duct 02. Acc. Parotid gland duct if present 03. Pterygoid process – Bet’ mandibular ramus and ptrygoid muscle 04. Glenoid process - Bet. Ext meatus and capsule of TM joint 05. Pre and post styloid processes in front related to int. carotid behind related to int. Jug. Vein

Structures passing through parotid 1. Facial nerve 2. Retromandibular vein 3. External carotid

Branching of facial nerve (Radiate like goose’s foot – Pes anserinus) Emerges from SM foramen Pierces post. Medial surface Lies superficial to Retromeandibualr vein & Ext. carotid art. Divides into 1. Temporo faicial division - Temporal Zygomatic 2. Cervico facial division - Buccal Marginal mandibular Cervical

Accessory parotid gland

Blood supply Arterial – branches of ext. carotid Veins - to ext. jugular vein Lymphatics – parotid nodes Nerve supply – Secretomotor from both Parasympathetic – Serous Inf. Salivatory nucleus - medulla (auriculo temporal) Sympathetic - Mucinous Sup. Cerv. ganglion (Ext. carotid art. ) Vasomotor

Applied anatomy Parotitis – ext capsule adherent – more painful Parotid abscess – horizontal incision Mixed parotid tumor – facial nerve not involved Frey’s syndrome – Penetrating wounds secretomotor fibres of auriculotemporal join with great auricular perspiration of skin covering parotid during eating

Sialography, Sialolith