Anatomy of Waldeyers Ring .pptx

Anatomy of Waldeyers Ring

1. Anatomy of Waldeyers Ring

2. Waldeye r’s Lymphatic Ring T he aggregations of lymphoid tissue underneath the epithelial lining of pharyngeal wall are called tonsils These aggregations together constitute an interrupted circle called Waldeyer’s ring , which forms the special feature of the interior the pharynx. They surround the commencement of air and food passages.

3. Formation of Waldeyers Ring The Waldeyer’s ring is formed by 1. Nasopharyngeal tonsil or the adenoids 2. Palatine tonsils or simply the tonsils 3. Lingual tonsil 4. Tubal tonsils (in fossa of Rosenmüller) 5. Lateral pharyngeal bands 6. Nodules (in posterior pharyngeal wall).

4. Nasopharyngeal Tonsil (Adenoids) It is a subepithelial collection of lymphoid tissue at the junction of roof and posterior wall of nasopharynx It causes the overlying mucous membrane to be thrown into radiating folds It increases in size up to the age of 6 years and then gradually atrophies.

5. Blood supply Adenoids receive their blood supply from: 1. Ascending palatine branch of facial. 2. Ascending pharyngeal branch of external carotid. 3. Pharyngeal branch of the third part of maxillary artery. 4. Ascending cervical branch of inferior thyroid artery of thyrocervical trunk.

6. Lymphatic drainage Lymphatics from the adenoid drain into upper jugular nodes directly or indirectly via retropharyngeal and parapharyngeal nodes. Nerve supply Nerve Supply is through CN IX and X. They carry sensation.Referred pain to ear due to adenoiditis is also mediated through them

7. Palatine tonsils Palatine tonsils are two in number Each tonsil is an ovoid mass of lymphoid tissue situated in the lateral wall of oropharynx between the anterior and posterior pillars. Parts of tonsil extend upwards into the soft palate, downwards into the base of tongue and anteriorly into palatoglossal arch. So actual size of the tonsil is bigger than the one that appears from its surface

8. BLOOD SUPPLY The tonsil is supplied by five arteries 1. Tonsillar branch of facial artery. This is the main artery. 2. Ascending pharyngeal artery from external carotid. 3. Ascending palatine, a branch of facial artery. 4. Dorsal linguae branches of lingual artery. 5. Descending palatine branch of maxillary artery. VENOUS DRAINAGE Veins from the tonsils drain into paratonsillar vein which joins the common facial vein and pharyngeal venous plexus.

9. LYMPHATIC DRAINAGE Lymphatics from the tonsil pierce the superior constrictor and drain into upper deep cervical nodes particularly the jugulodigastric (tonsillar) node situated below the angle of mandible. NERVE SUPPLY Lesser palatine branches of sphenopalatine ganglion (CN V) and glossopharyngeal nerve provide sensory nerve supply.

10. Lingual tonsils It forms the Anterior wall of Oropharynx Situated on either side of the base of the tongue They may show compensatory enlargement following tonsillectomy or may be the seat of infection

11. Tubal Tonsil It is collection of subepithelial lymphoid tissue situated at the tubal elevation. It is continuous with adenoid tissue and forms a part of the Waldeyer’s ring. When enlarged due to infection, it causes eustachian tube occlusion.

12. Functions 1. Prevents the invasion of microorganisms from entering the air and food passages 2.Helps in the defense mechanism of the respiratory and alimentary systems. 3.Formation of Lymphocytes and Antibodies

13. Clinical significance Tonsillitis : This inflammatory condition of the tonsils is due to viral or bacterial infections. It presents with Throat infection,Fever,Hoarseness or loss of voice,Issues with swallowing A visible white or yellow coating on the tonsils upon examination Treatment includes painkillers, as well as antibiotics (for immunocompromised, severe or painful cases only).

14. Tonsillectomy : This is a surgical procedure where the palatine tonsils are removed from each side of the oropharynx. The surgery is usually needed due to: Airway obstruction from enlarged tonsils, Sleep apnoea ,Snoring , Recurrent tonsillitis Other tonsils can also be removed in the same procedure. As the tonsils are highly vascularized, they bleed heavily during the surgery. Hydration and analgesics are essential for good recovery

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