Sits between two arches of the soft palate, the palatoglossal in front and the palatopharyngeal behind
The palatine tonsil in the tonsillar fossa, between the anterior and posterior pillars
Anatomy · Head, neck & teeth
Tonsil
The lymphoid tissue on each side of the throat
Oropharynx · Waldeyer's ring
Usually meaning the palatine tonsil: an almond-sized mass of lymphoid tissue lying in a triangular recess (the tonsillar fossa) on each side of the back of the mouth, between the palatoglossal fold in front and the palatopharyngeal fold behind. Its surface is pitted with deep crypts. It is the largest of the tonsils that together form Waldeyer's ring, a defensive collar of lymphoid tissue round the entrance to the throat.
How to spot them
- ▸A pink oval mass on either side of the throat, between two vertical mucosal folds (the pillars of the fauces)
- ▸Surface pitted with crypts that can trap debris (tonsilloliths)
- ▸The largest in childhood, shrinking after puberty
- ▸Its deep surface lies on the superior pharyngeal constrictor, close to the glossopharyngeal nerve
What to know
A ring of lymphoid tissue round the entrance to the throat, named after a German anatomist who described it in 1884 (1884)
Waldeyer's ring — palatine, lingual, tubal and pharyngeal tonsils (adenoids), after Wilhelm von Waldeyer-Hartz
After its removal, pain is often felt in the ear because the glossopharyngeal nerve supplies both the throat and the middle-ear cavity
Referred otalgia after tonsillectomy — Jacobson's nerve
A collection of pus between it and the wall of the throat, causing a muffled voice, difficulty opening the mouth and a deviated uvula
Peritonsillar abscess, or quinsy
Its blood supply chiefly comes from a branch of the facial artery, and bleeding after its removal usually arises from the paratonsillar vein
The tonsil's blood supply — facial artery (tonsillar branch)
Unlike a lymph node it has no afferent lymphatics; lymph leaves to the jugulodigastric node
The palatine tonsil drains to the jugulodigastric (tonsillar) node
Swollen and speckled with pus in a sore throat, the pair may enlarge until they almost meet in the midline
Acute tonsillitis, very common in children; so-called kissing tonsils
Key ideas
- Tonsil tissue samples antigens from air and food through its crypts, a first line of immune defence at the entrance to the digestive and respiratory tracts.
- The tonsil is not a lymph node: it has crypts rather than afferent lymphatics, and its antigens come straight from the mouth.
Quick-fire facts
- •Each palatine tonsil has about 10–30 crypts and is covered by stratified squamous epithelium
- •Waldeyer's ring comprises the paired palatine and tubal tonsils, the single pharyngeal tonsil (adenoids) and the single lingual tonsil
- •The tonsillar bed lies against the superior constrictor, with the glossopharyngeal nerve nearby
- •Largest in childhood, at about 4–8 years, and generally shrinking after puberty
- •Tonsillectomy is one of the commonest operations in children; UK guidance links it to frequent, well-documented episodes of severe tonsillitis
- •Most sore throats are viral; bacterial tonsillitis is often due to group A streptococcus
- •Tonsilloliths ('tonsil stones') are calcified debris in the crypts, often causing bad breath
- •Do not confuse with the cerebellar tonsils, which lie at the base of the cerebellum and can herniate through the foramen magnum
Drill it — 7 cards
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Sources
- TeachMeAnatomy — The Tonsils (Waldeyer's Ring)
- NHS — Tonsillitis