Anterior part of the alimentary canal. 1. Isthmus of the fauces 2. Tonsils 3. Salivary glands minor and major salivary glands 4. Pharynx 5.

Transcription

1 Anterior part of the alimentary canal 1. Isthmus of the fauces 2. Tonsils 3. Salivary glands minor and major salivary glands 4. Pharynx 5. Esophagus

2 Oropharyngeal isthmus Isthmus of the fauces, isthmus faucium (Lat. a vestibule of an ancient Roman house): palatine velum, velum palatinum palatine uvula, uvula palatina palatoglossal arch palatopharyngeal arch 2

3 von Waldeyer ( ) Waldeyer s ring NALT Nasal-Associated Lymphoid Tissue Anulus lymphoides Waldeyeri: lingual tonsil pharyngeal tonsil (tonsilla adenoidea) tubal tonsils palatine tonsils 3

4 Lymphoid tissue lymphoepithelial organs MALT Mucosa Associated Lymphatic Tissue 4

5 Palatine tonsils, tonsillae palatinae Macroscopic anatomy: paired structures egg-like shape 25х15х20 mm placed in triangular recess(tonsillar sinus) supratonsillar fossa plica semilunaris, plica triangularis capsule, capsula tonsillae 5

6 Palatine tonsils, tonsillae palatinae Microscopic anatomy: lamina epithelialis stratified squamous epithelium tonsillar crypts desquamated epithelial cells lamina propria loose connective tissue lymphoid nodules tela submucosa capsule trabeculae lobules 6

7 Blood vessels of palatine tonsils Blood supply: tonsillar branches of facial artery ascending palatine artery ascending pharyngeal artery Venous drainage: palatine vein, pharyngeal veins facial vein internal jugular vein Lymphatic drainage: submandibular nodes lateral cervical nodes 7

8 Salivary glands Minor salivary glands, glandulae salivariae minores: minor glands mixed(seromucous) glands labial glands buccal glands molar glands anterior linglual(nuhn s) glands serous glands gustatory (von Ebner s) glands mucous glands palatine glands posterior lingual(weber s) glands produceonly5-8%ofthetotaloutput 8

9 Salivary glands Major salivary glands, glandulae salivariae majores: parotid gland, glandula parotidea (parotis) submanibular gland, glandula submandibularis sublingual gland, glandula submandibularis 9

10 Nicolas Steno (Niels Stensen) ( ) Parotid gland, gl. parotidea Macroscopic anatomy: located subcutaneously in the parotideomasseteric region the largest salivary gland g has own fascia, fascia parotidea roughly wedge shaped and lobulated superficial and deep lobes internally: end branches of the external carotid artery retromandibular vein deep parotid lymphoid nodes parotid plexus of facial nerve auriculotemporal nerve (V 3 ) parotid duct(stensen s duct) accessory parotid gland 10

11 Parotid gland, gl. parotidea Microscopic anatomy: enclosed within a capsule irregular, lobulated mass a purely serous gland (watery secretion) salivary ducts mostly intercalated ducts adipose tissue fat cells 11

12 Submandibular gland, gl. submandibularis Macroscopic anatomy: under the oral floor in the submandibular trigone weight 15 g d=1.5-2 cm (the size of a walnut); U-shaped; smaller deep process covered by fascia cervicalis superficialis lobulated structure 8-10 lobes three surfaces submandibular (Wharton s) duct 5-6 cm caruncula sublingualis blood supply facial and lingual arteries lymphatic drainage submandibular nodes innervation intermediate nerve, superior cervical ganglion 12

13 Submandibular gland, gl. submandibularis Microscopic anatomy: enclosed within a capsule, lobulated mixed (seromucous) gland with predominant serous acini Giannuzzi s demilunes or Heidenhain crescents duct system mostly striated ducts 13

14 Sublingual gland, gl. sublingualis Macroscopic anatomy: along the sublingual fold, plica sublingualis the smallest one weight 3-5 g flattened, almond-shaped covered by a thin capsule lobulated mass 4-16 lobules a group of single glands: anterior major sublingual gland major sublingual duct caruncula sublingualis smaller sublingual ducts sublingual fold blood supply sublingual artery venous drainage internal jugular vein lymphatic drainage submandibular nodes innervation intermediate nerve, superior cervical ganglion 14

15 Sublingual gland, gl. sublingualis Microscopic anatomy: surrounded by a dense capsule, lobulated predominantly tubulo-alveolar (acinar) gland mixed (seromucous) gland consisting mostly of mucous (60%) acini minor sublingual glands; serous caps, demilunes (30% of total gland volume) excretory ducts 8-20 in number 15

16 Throat, pharynx part of the digestive and the respiratory systems the common channel for deglutition (swallowing) and respiration important also in vocalization musculomembranous cone-shaped tube: height cm diameter upper part: 3.5 cm lower part: 1.5 cm 16

17 Topography base of skull 6 th cervical vertebra nasal cavity oral cavity larynx cervical fascia (prevetrebral layer) retropharyngeal space lateral: cervical lymph nodes posterior mediastinum neurovascular bundle 17

18 Topography base of skull 6 th cervical vertebra nasal cavity oral cavity larynx cervical fascia (prevetrebral layer) retropharyngeal space lateral: cervical lymph nodes posterior mediastinum neurovascular bundle 18

19 Macroscopic anatomy upper (nasal) part middle (oral) part lower (laryngeal) part 19

20 Nasal part of the pharynx synonyms: nasopharynx, epipharynx anterior boundary: nasal conchae lateral wall: pharyngeal opening of the auditory tube cranial boundary: pharyngeal fornix pharyngeal tonsil(adenoides) 20

21 Oral part of the pharynx synonyms: oropharynx, mesopharynx anterior boundary: palatopharyngeal arch palatoglossal arch cranial boundary: velum palatinum caudal boundary: upper part of the epiglottis epiglottic vallecula 21

22 Laryngeal part of the pharynx synonyms : laryngopharynx, hypopharynx cranial boundary: ventral boundary: epiglottis aditus laryngis dorsal boundary: constrictio pharyngoesophagealis 22

23 Histological structure Lamina epithelialis: stratified squamous non-keratinizing epithelium, excl. the nasal part pseudostratified ciliated columnar epithelium with goblet cells Lamina propria: a high density of fibrillar elements fibrous membrane rich in elastic fibers elastic membrane contains glands: nasal part seromucous glands oral and laryngeal parts mucous (pharyngeal) glands Tela submucosa: in the lateral walls of the nasal part close to the esophagus 23

24 Pharyngeal musculature striated muscles: origin pharyngeal arches tunica muscularis pharyngis: internal longitudinal layer external circular layer two functional groups: three pharyngeal constrictors two longitudinal elevators 24

25 Vessels of the pharynx Arterial blood supply: a. thyroidea superior a. palatina descendens a. palatina ascendens a. facialis ramus tonsillaris a. thyroidea inferior a. pharyngea ascendens Venous drainage: plexus venosus pharyngeus vv. pharyngeales into the v. jugularis interna Lymphatic drainage: retropharyngeal lymph nodes deep cervical lymph nodes 25

26 Innervation of the pharynx Somatosensory innervation: trigeminal nerve Pharyngeal plexus: motor, sensory and parasympathetic innervation: vagus nerve glossopharyngeal nerve sympathetic innervation: superior cervical ganglion of the trunk sympathetic 26

27 The gullet, oesophagus Straight muscular tube about cm long to carry food, liquids, and saliva from the mouth to the stomach: begins in the neck at the level of C 6 passes through the thoracic cavity and piercesthediaphragm at the Th 10 level ends at the cardiac orifice of the stomach at the Th 11 level 27

28 Macroscopic anatomy Three anatomical parts: cervical part 5-6 cm thoracic part cm abdominal part 1-4 cm 28

29 Anatomical constrictions Three anatomical constrictions: pharyngeal 15cmfromtheincisorteeth bronchial 24 cm from the incisors diaphragmatic 40 cm from the incisors NB:The sites of these constrictions are clinically important in connection with the passage of instruments along the esophagus gastroscopy! 29

30 Physiological constrictions Two physiological constrictions formed by contraction of its musculature 1. Aortal constriction where esophagus is crossed by the aortic arch 2. Cardiac sphincter just before entering the stomach cardia 30

31 The closing mechanism between the stomach and esophagus 1. contraction of the spiral musculature 2. submucosal venous plexus esophagitis 3. elastic nature of the phrenoesophageal ligament esophagitis 4. a pressure difference between the abdominal and thoracic cavities Clinical significance: insufficient closing mechanism gastroesophageal (acid) reflux disease heartburn 31

32 Histological structure Lamina epithelialis mucosae: multilayered (20-24 cell layers) nonkeratinizing squamous epithelium no distinct border at the transition into the stomach intestinal metaplasia (columnar epithelium) Lamina propria mucosae: collagen and elastic fibers esophageal cardiac glands venous plexus lymphatic nodules Lamina muscularis mucosae: longitudinally organized smooth muscle Barrett oesophagus 32

33 Histological structure Tela submucosa: wide layer with longitudinal folds contains esophageal glands proper submucosal (Meissner s) plexus Tunica muscularis transition zone: inner circular layer (stratum circulare) outer longitudinal layer (stratum longitudinale) between them myenteric (Auerbach s) plexus Tunica adventitia: loose, fibrous connective tissue Clinical significance: muscular weakness esophageal diverticula! 33

34 Vessels of the esophagus Blood supply esophageal branches: cervical part: inferior thyroid artery thoracic part: aorta, intercostal arteries abdominal part: left gastric artery Venous drainage: brachiocephalic vein azygos vein hemiazygos vein hepatic portal vein drain into the: superior vena cava inferior vena cava portal vein Clinical significance: portal hypertension esophageal varices! 34

35 Innervation of the esophagus motor, sensory and parasympathetic innervation: vagus nerve vagal trunks sympathetic innervation: sympathetic trunk 35

36 Thank you... 36