China
Africa
Explore chapters and articles related to this topic
Data and Picture Interpretation Stations: Cases 1–45
Published in Peter Kullar, Joseph Manjaly, Livy Kenyon, Joseph Manjaly, Peter Kullar, Joseph Manjaly, Peter Kullar, ENT OSCEs, 2023
Peter Kullar, Joseph Manjaly, Livy Kenyon, Joseph Manjaly, Peter Kullar, Joseph Manjaly, Peter Kullar
The pharyngeal tonsils are part of Waldeyer's ring of tonsillar tissue which also includes the adenoid tissue, tubal tonsils and lingual tonsils. Tonsillitis can be viral or bacterial. Common pathogens include adenovirus, Epstein-Barr virus, enteroviruses, and Group A beta haemolytic streptococcus (GABHS). GABHS is best treated with penicillin, and amoxicillin should be avoided as it can cause a salmon-coloured maculopapular rash if the patient has EBV. Complications of tonsillitis include peritonsillar, parapharyngeal and retropharyngeal abscesses, and systemic complications include scarlet fever, rheumatic fever and post-streptococcal glomerulonephritis.
SBA Answers and Explanations
Published in Vivian A. Elwell, Jonathan M. Fishman, Rajat Chowdhury, SBAs for the MRCS Part A, 2018
Vivian A. Elwell, Jonathan M. Fishman, Rajat Chowdhury
The palatine tonsils (‘tonsils’) are a large collection of lymphoid tissue that project into the oropharynx from the tonsillar fossa, between the palatoglossal arch (in front) and the palatopharyngeal arch (behind). They are most prominent in early life and regress in later years as the lymphoid tissue atrophies. The surface marking is medial to the lower masseter. The palatine, lingual, pharyngeal (‘adenoids’), and tubal tonsils collectively form an interrupted circle of protective lymphoid tissue at the upper end of the respiratory and alimentary tracts known as Waldeyer’s ring. This area has a role in the priming of lymphocytes for antigens during the early years of life.
Anatomy and Embryology of the Mouth and Dentition
Published in John C Watkinson, Raymond W Clarke, Terry M Jones, Vinidh Paleri, Nicholas White, Tim Woolford, Head & Neck Surgery Plastic Surgery, 2018
The palatine tonsil is a mass of lymphoid tissue situated in the lateral wall of the oropharynx, where it lies within the tonsillar fossa between the diverging palatopharyngeal and palatoglossal arches. It forms the anteroinferior part of Waldeyer’s ring of lymphoid tissue. This ring surrounds the openings into the digestive and respiratory tracts and consists of the palatine and tubal tonsils laterally, the nasopharyngeal tonsil (adenoids) and smaller collections of lymphoid tissue in the intertonsillar intervals posterosuperiorly, and the lingual tonsil inferiorly.
Hodgkin lymphoma involving extranodal sites in head and neck: report of twenty-nine cases and review of three-hundred and fifty-seven cases
Published in Hematology, 2021
Saad Akhtar, Yassir Khafaga, Wael Edesa, Mustafa Al-Mubarak, M. Shahzad Rauf, Irfan Maghfoor
Hodgkin lymphoma (HL) represents 3.5% of all the cancers diagnosed in the Kingdom of Saudi Arabia [1]. Most HL arises in a lymph node and current multiagent anthracycline-based chemotherapy with or without radiation therapy (RT) can cure 73%–98% patients depending on the stage and other risk factors [2]. Waldeyer’s ring (WR) is an anatomical term collectively describing the lymphoid tissue in the pharynx. WR consists of pharyngeal tonsils (adenoid), tubal tonsil (where each Eustachian tube open), palatine tonsils (commonly called ‘the tonsils’ in the oropharynx), and lingual tonsils (on the posterior part of the tongue). It is considered an extranodal site but not an extralymphatic site [3]. Although the head and neck area lymph nodes are the most common site of disease, unlike non-Hodgkin lymphoma, the involvement of extranodal head and neck sites (ENHNS) including WR is an uncommon observation.
Subunit-based mucosal vaccine delivery systems for pulmonary delivery - Are they feasible?
Published in Drug Development and Industrial Pharmacy, 2019
Nirmal Marasini, Lisa M. Kaminskas
The URT (nasopharynx) is the primary site of contact for inhaled pathogens. Several pathogens, including Mycoplasma pneumonia, Streptococcus aureus, Haemophilus influenza, Staphylococcus aureus and Streptococcus pneumonia commonly infiltrate the URT [17]. The URT is highly vascularized and contains a dense network of mucosal-associated lymphoid tissue (MALT). In humans, the URT comprises the Waldeyer’s ring (nasopharyngeal or adenoid tonsils, paired tubal tonsils, paired palatine tonsil and lingual tonsil), which functions as a major lymphatic site. There are, however, major differences between URT immune tissues in humans and rodents, which are primarily used as models for studying respiratory infections. Rodents lack tonsils and contain nasal associated lymphoid tissues (NALT). Rodent NALTs have well-organized lymphoid tissue aggregates that are located near the entrance of the nasopharyngeal duct and less organized diffuse lymphoid structures in the lining of the nasal passage [18,19]. The NALT system is important for vaccine administration, as it is comprised of distinct populations of several immune cells, such as follicular B-cells, T-cells (CD4+ and CD8+ T cells), and antigen presenting cells (APC) for the induction of humoral and cell-mediated immunity [20,21]. NALT and the nasal passages represent major inductive sites for the initiation of mucosal IgA responses. A number of microfold cells (M-cells), which are similar to the M-cells in Peyer’s patch in the intestine, are present in the epithelial region of the URT and efficiently sample airway particulate antigens [22]. Dendritic cells (DC) are the most efficient APCs, having the unique ability to regulate an adaptive immune response. The location of DCs is highly dependent on their function, with specialized subsets in the conducting pathway, and others in the lungs [23]. When antigens are trapped and internalized by DCs, they are transported to draining lymph nodes for presentation to antigen specific T cells that elicit adaptive immune pathways (Figure 1).