Tyler Scoresby, MD
Tonsillectomy and adenoidectomy are two of the most commonly performed major surgeries in the United States. As such, a thorough understanding of the anatomy, pathophysiology, and procedure is essential to the otolaryngologist.
History of the Procedure
Tonsillectomy was first described by Celsus at around 50 BC. Adenoidectomy was likely first performed by Wilhelm Meyer in the late 1800s. The large discrepancy between the two is likely attributable to the relatively hidden location of the adenoids in the nasopharynx. The two procedures began to be routinely performed together in the early 1900s. “Routinely” in this instance is not an understatement; the combined procedure became nearly universal among children at this time. Indications broadly included anorexia, mental retardation, enuresis or simply to promote good health. While these indications may seem outlandish now, they may be based in sound medical decision making. Children may fail to thrive if they have chronically sore throats or severe obstructive sleep apnea (OSA). OSA has also been linked with enuresis. Children who hear poorly because of chronic otitis media may have speech delay and be mistaken for mentally retarded. In the 1930s and 40s the incidence of the procedure declined somewhat as antibiotics became available.
Relevant Anatomy
The lyphoid tissue commonly known as the adenoids are also called the pharyngeal tonsils. These along with the palatine tonsils (generally just called “tonsils”) and the lingual tonsils make up Waldeyer’s ring. The adenoid pad lies just over the base of skull and clivus between each torus tubarius. The (palatine) tonsils are located in the lateral oropharynx between the palatoglossis (the anterior pillar) and the palatopharyngeus (posterior pillar) muscles. The deep margin is the superior constrictor and inferiorly they may be continuous with the lingual tonsils. The tonsils have a rich vascular supply including the ascending pharyngeal, lesser palatine, facial artery, lingual and ascending palatine arteries.
On histology, the tonsils contain 10-30 crypts lined by antigen processing stratified squamous epithelium. They have germinal centers as in other lymph tissue.
Immunology and Microbiology
Because of the strategic location of this lymphatic tissue at the entry of the respiratory and alimentary tracts, they bear an onslaught of antigens. They actively produce lymphocytes and immunglobulins. Healthy tonsils and adenoids thus clearly confer immune protection. Diseased tonsils, however, perform protective functions poorly, and actually harbor pathogens.
Group A Beta-hemolytic streptococcus is classically associated with acute tonsillitis. However, a multitude of organisms are commonly cultured in acute and chronic tonsillitis. Bacteria include Groups B, C, G Strep; H. Influenza; S. pneumoniae; M. Cattarrhalis; S. Aureus; Neisseria, Bacteroides, Peptococcus, Peptostreptococcus and Actinomyces. Viruses found in tonstil tissue include EBV, Adenovirus, Influenza A and B, Herpes, RSV and Parainfluenza.
Tonsil and Adenoid Pathology
The adenoid pad becomes colonized by bacteria during the first few weeks of life. They enlarge in response to antigens at around age 5-7. If they are to become symptomatic they will typically do so around age 18-24 months. By adolescence, they typically regress in size.
Acute adenoiditis is characterized by purulent rhinorrhea, nasal obstruction, fever, otitis media, snoring, and halitosis. Recurrent and chronic adenoiditis are also described with the same symptoms in either multiple episodes or persistent symptoms respectively. Because the symptoms are rather nonspecific, there is a fairly large differential diagnosis including allergy, septal deviation, choanal stenosis, chronic rhinosinusitis, and esophageal reflux.
Acute tonsillitis is characterized by fever, dysphagia, lymphadenopathy, red or exudative tonsils and pain. Recurrent tonsillitis has been described classically as 7 episodes in 1 year, 5 in 2 consecutive years or 3 per year in 3 years. These strict criteria are not always applied and recent studies indicate that tonsillectomy using less stringent criteria can still reduce the level of recurrence. Chronic tonsillitis is indicated by chronic sore throat, malodorous breath, tonsilliths, persistent peritonsillar erythema and persistent cervical lymphadenopathy.
The harboring of bacteria in the adenoids and tonsils can indeed cause recurrent infections. However, in children, a more frequent indication for excision is their obstructive size. Excessive hyperplasia of the adenoids and tonsils in childhood can lead to obstructive sleep apnea, and this is a much stronger indication for their excision.
Evaluation
A thorough history regarding the adenoids should include questioning regarding obligate mouth breathing, snoring, hyponasal speech, rhinorrhea and chronic nocturnal cough. In regards to the tonsils, a thorough history of episodes of infection should be obtained. As the otolaryngologist does not frequently see acute tonsillitis, a history of infection given by the parents or the primary care provider must frequently form the basis for surgery. This history is often over- or underestimated, however. Questioning should include obstructive symptoms such as loud snoring, nocturnal choking, coughing, frequent awakenings, enuresis, dysphagia, daytime somnolence, non-specific behavioral abnormalities or developmental delay. Given the risk of bleeding, in tonsillectomy, a family history of bleeding diatheses must be obtained.
Physical exam in obstructive adenoid disease will often reveal an “adenoid facies” which is described as having an open mouth and flattened midface and dark circles under the eyes. Anterior rhinoscopy will not reveal adenoid hypertrophy but can evaluate other causes of nasal obstruction such as septal deviation or allergy. Flexible nasopharyngoscopy is helpful in evaluating adenoid hypertrophy although this is not routinely performed in children. A palate exam should also be included to check for a submucous cleft palate. This can occur in 1 in 1200 children and if an adenoidectomy is performed in these children they may develop velopharyngeal insufficiency. A lateral neck film is also still occasionally used to evaluate the degree of obstruction caused by the adenoids. Chronically infected tonsils may show peritonsillar erythema, cervical lymphadenopathy, tonsilliths or a decreased number of crypts. Serious tonsillar obstruction may present with failure to thrive or cor pulmonale.
A polysonmogram should be performed if the diagnosis is unclear or if there is an unusual risk for surgery. It should be noted that the criteria for obstructive sleep apnea is different for children; it is defined as more than 1 event per hour with a desaturation of less than 92%.
Indications for Surgery
The absolute indications for tonsillectomy are:
-Enlarged tonsils causing upper airway obstruction, severe dysphagia, sleep disorders, or cardiopulmonary complications
-Peritonsillar abscess that is unresponsive to medical management and drainage documented by surgeon
-Tonsillitis resulting in febrile convulsions
-Tonsils requiring biopsy to define tissue pathology
Relative indications are:
-Infection: 7 or more in one year, 5 or more in each of two years, or 3 or more in each of 3 years
-Persistent foul taste or breath not responsive to medical therapy
-Chronic tonisllitis in a strep carrier that does not improve with beta-lactamase resistant antibiotic
For adenoidectomy the indications are:
-Prevention of recurrent/chronic otitis media
-Obstructive adenoids
-Recurent/chronic sinusitis in children
-Recurrent/chronic adendoiditis
Methods of Surgery
There are several ways to excise the tonsils and adenoids. These include the cold steel technique (use of scissors, scalpels and curettes), monopolar cautery, bipolar cautery, radiofrequency ablation, harmonic scalpel with vibrating blades, microdebrider laser, and coblation. Nnumerous studies have been conducted that attempt to compare the various techniques with regard to operative time, post-operative pain, time to complete recovery, and post operative complications. Given the conflicting results of these studies, which technique is best remains a personal preference of the surgeon.
Complications
Tonsillectomy can result in pain, dehydration, post operative airway obstruction caused by hematoma or uvular edema, and local trauma to oral tissues. Pulmonary edema may also occur in patients who had true airway obstruction prior to surgery. One of the major complications is post-tonsillectomy hemorrhage which is estimated to occur in 2-3% of patients. 1 in 40,000 die from severe hemorrhage. The highest incidence of bleeding is 5-8 days post operatively.
Bleeding may also occur after adenoidectomy but it is typically in the immediate post-operative period), Adenoidectomy may also cause velopharyngeal insufficiency, in which the patient’s palate does not approximate the posterior wall of the pharynx on speaking or eating, resulting in a hypernasal voice or nasal regurgitation of food or drink. This complication is fairly common but typically resolves in less that 2 months. Persistent VPI occurs in 0.03-0.06% of patients and requires speech therapy and/or surgery. Occasionally adenoidectomy can result in torticollis, nasopharyngeal stensosis and atlanto-axial subluxation from inflammation and decalcification of the anterior transverse ligament between C1 and C2.
Special Considerations in Tonsillectomy and Adenoidectomy
Certain children are at increased risk of complications from tonsillectomy or adenoidectomy and such patients should be identified and undergo surgery only after careful consideration. Some children are at significant risk for VPI if adenoidectomy is performed. These include any child with cleft palate or syndrome associated with cleft palate such as Treacher-Collins, Pierre-Robin, and velocardiofacial syndrome. Children with neuromuscular disorders such as Arnold-Chiari malformation, Down Syndrome and Myotonic Dystrophy are also at increased risk of VPI.
Ten percent of children with Down Syndrome may also have congenital atlanto-axial instability and are at risk of subluxation and or paralysis if their neck is extended in surgery.
Any child with neuromuscular disorder is also at risk for aspiration or post operative airway obstruction associated with general anesthesia.
