Waldeyer's tonsillar ring (pharyngeal lymphoid ring, Waldeyer's lymphatic ring, or tonsillar ring) is a ringed arrangement of lymphoid organs in the

pharynx The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its ...

. Waldeyer's ring surrounds the naso- and

oropharynx The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struc ...

, with some of its tonsillar tissue located above and some below the

soft palate The soft palate (also known as the velum, palatal velum, or muscular palate) is, in mammals, the soft tissue constituting the back of the roof of the mouth. The soft palate is part of the palate of the mouth; the other part is the hard palate. ...

(and to the back of the mouth cavity).

Structure

The ring consists of the (from top to bottom): * 1 pharyngeal tonsil (or "adenoid"), located on the roof of the nasopharynx, under the sphenoid bone. * 2 tubal tonsils on each side, where each

auditory tube Auditory means of or relating to the process of hearing: * Auditory system, the neurological structures and pathways of sound perception ** Auditory bulla, part of auditory system found in mammals other than primates ** Auditory nerve, also known ...

opens into the nasopharynx * 2

palatine tonsil Palatine tonsils, commonly called the tonsils and occasionally called the faucial tonsils, are tonsils located on the left and right sides at the back of the throat, which can often be seen as flesh-colored, pinkish lumps. Tonsils only present a ...

s (commonly called "the tonsils") located in the oropharynx * lingual tonsils, a collection of lymphatic tissue located on the back part of the

tongue The tongue is a muscular organ in the mouth of a typical tetrapod. It manipulates food for mastication and swallowing as part of the digestive process, and is the primary organ of taste. The tongue's upper surface (dorsum) is covered by taste bu ...

Terminology

Some authors speak of two pharyngeal tonsils/two adenoids. These authors simply look at the left and right halves of the pharyngeal tonsil as two tonsils. Many authors also speak of lingual tonsils (in the plural), because this accumulation of lymphoid tissue consists of a number of little prominences – many smaller rounded masses. Whether to collectively call all these a single tonsil or separate tonsils is to an extent an arbitrary decision.

Variation

There also normally is a good amount of

mucosa A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. It is ...

-associated

lymphoid tissue The lymphatic system, or lymphoid system, is an organ system in vertebrates that is part of the immune system, and complementary to the circulatory system. It consists of a large network of lymphatic vessels, lymph nodes, lymphatic or lymphoid ...

(

MALT Malt is germinated cereal grain that has been dried in a process known as " malting". The grain is made to germinate by soaking in water and is then halted from germinating further by drying with hot air. Malted grain is used to make beer, ...

) present between all these tonsils (intertonsillar) around the ring, and more of this lymphoid tissue can variably be found more or less throughout at least the naso- and oropharynx.

Development

The tubal tonsils usually develops from an accumulation of lymphoid tissue in the pharyngeal tonsil.

Clinical significance

The

s when inflamed/swollen, more common in children, can obstruct respiration. Inflammation of the tonsils is called

tonsillitis Tonsillitis is inflammation of the tonsils in the upper part of the throat. It can be acute or chronic. Acute tonsillitis typically has a rapid onset. Symptoms may include sore throat, fever, enlargement of the tonsils, trouble swallowing, a ...

and removal is called

tonsillectomy Tonsillectomy is a surgical procedure in which both palatine tonsils are fully removed from the back of the throat. The procedure is mainly performed for recurrent tonsillitis, throat infections and obstructive sleep apnea (OSA). For those with ...

Etymology of Waldeyer’s ring

Waldeyer's ring was named after the nineteenth-century

German German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ger ...

anatomist Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having it ...

Heinrich Wilhelm Gottfried von Waldeyer-Hartz Heinrich Wilhelm Gottfried von Waldeyer-Hartz (6 October 1836 – 23 January 1921) was a German anatomist, known for summarizing neuron doctrine, neuron theory and for naming the chromosome. He is also remembered by anatomical structures of the ...

Other animals

Some animals, but not humans, have one or two additional tonsils: * Soft palate tonsil * Paraepiglottic tonsil

References

{{Lymphatic organ anatomy Lymphatics of the head and neck Tonsil Lymphoid organ Pharynx